Gary Oliver
Senior Clerk
+44 (0) 207 822 7325
Jason is widely regarded as a leading senior junior, with a diverse and busy practice. He has particular expertise in public and human rights law, public international law, competition law, EU law, sanctions, sports law, media and data protection law, and immigration law. Jason combines a strong commercial practice with an extensive publicly funded and pro bono human rights practice, drawing on his academic expertise in this area. His clients include individuals, companies, States, current and former Heads of State and Heads of Government, members of the Royal Family, UK Government Departments, international organisations and NGOs. Jason regularly appears in the highest appellate courts, including the Court of Appeal, the Supreme Court, the European Court of Human Rights, and the Court of Justice of the European Union. He has appeared in 22 cases in the Supreme Court, before the General Court and Court of Justice in over twenty-five cases, and before the European Court of Human Rights in more than a dozen cases. Jason has extensive advocacy experience, and regularly appears unled, including in the High Court and the General Court of the European Union.
Jason is ranked as a leading junior in eight practice areas in the leading independent legal directories, Legal 500, Chambers UK and Chambers Global, including Band 1 for Administrative and Public Law, Civil Liberties and Sanctions Law. Jason was shortlisted for Human Rights and Public Law Junior of the Year in the Chambers UK Bar Awards 2022 and for EU and Competition Junior of the year in the Legal 500 Awards 2020. In 2021, Jason was featured on The Lawyer's Hot 100 List, where he was described as "one of the most sought after juniors in the business". In 2018, Jason won the World's ECR's young practitioner of the year award.
Jason is a member of the Attorney General's A Panel of Counsel, the Attorney General's PIL Panel of Counsel, and the Equality & Human Rights Commission's Panel of Counsel. In 2018 he was appointed a trustee of the AIRE Centre.
In addition to this London practice, Jason is a member of the Bar of Ireland and the Law Library of Ireland.
Recent highlights of Jason's practice include:
Recent comments in the directories include:
Prior to joining Chambers, Jason was an associate in the commercial litigation team at Mallesons Stephen Jaques (now King & Wood Mallesons) in Australia, where he had a broad commercial litigation practice. In addition to this experience as a commercial litigation solicitor, Jason has taught and published widely in the areas of public international law, public law and human rights, and international refugee law. He is a Research Associate at the Refugee Studies Centre at the University of Oxford. His monograph, The Child in International Refugee Law was published by Cambridge University Press in 2017, and was shortlisted for the triennial Inner Temple Book Prize.
Jason is recognised as a leading public law junior. He was shortlisted for Human Rights and Public Law Junior of the Year in the Chambers UK Bar Awards 2022. His clients include individuals, companies, States, current and former Heads of State and Heads of Government, members of the Royal Family, UK Government Departments, international organisations and NGOs. He regularly acts in high-profile litigation both for and against the UK Government. He has also acted in public law cases in Hong Kong, Singapore, the BVI and the Cayman Islands. Jason has particular expertise and experience in public law cases with a cross-over with commercial law, competition law and EU law. He appears regularly in the Administrative and Appellate Courts, and has been instructed in 22 cases before the Supreme Court (the majority of which have raised public law issues).
Jason is a member of the Attorney General’s A Panel of Counsel, and the Attorney General's PIL Panel of Counsel.
“He is just phenomenal; really clear, thorough and creative.”
Chambers and Partners, 2023
“He is amazing. He's knowledgeable beyond belief, he's a fantastic advocate and he's so meticulous in his preparation.”
Chambers and Partners, 2023
“He is just superb, he is a future star of the Bar. He's got an eye-watering work ethic and is always calm and collected.”
Chambers and Partners, 2023
“He's fantastically bright and provides a great degree of service.”
Chambers and Partners, 2022
“Jason is a superb junior who is much in demand with clients.”
Legal 500, 2022
“His advice and drafting are clear, well reasoned and tailored to the client's commercial objectives.”
Chambers and Partners, 2021
“His writing is among the best I've seen at the Bar.”
Chambers and Partners, 2021
“Extremely meticulous, client-friendly, and has an exceptional knowledge of EU and public law.”
Legal 500, 2021
Jason is acting for the former Prime Minister, Boris Johnson MP, in proceedings before the Privileges Committee relating to the investigation into whether the former Prime Minister misled Parliament over ‘partygate’ allegations (with Lord Pannick KC).
Jason is acting for the 11 lead refugee claimants in challenge to the Secretary of State’s Rwanda removal policy. Jason was part of the team which secured interim relief from the European Court of Human Rights.
Jason is acting for Annington in its judicial review challenge to decisions of the Ministry of Defence relating to enfranchisement of service family accommodation (listed as one of the top 20 cases for 2023) (with Monica Carss-Frisk KC).
Jason is acting for the Law Society in its challenge to the UK Government’s failure to implement the findings of the Bellamy Review into legal aid (with Tom de la Mare KC).
Jason acted for the Foreign Office in successfully defending the first s.38 challenge to a decision to designate an individual pursuant to the Sanctions and Anti-Money Laundering Act 2018. The judgment addressed both the relevant standard of proof, and the applicable standard of review (with Sir James Eadie KC).
Jason is acting for VW in judicial review challenge against the CMA to the extraterritorial scope of the Competition Act 1998. VW succeeded at first instance, and the CMA has been granted permission to appeal (with Brian Kennelly KC).
Jason is acting for the Home Secretary in Supreme Court in an appeal concerning whether the Public Sector Equality Duty in s.149 has extraterritorial effect (in the context of the Syrian refugee resettlement scheme) (with Sir James Eadie KC).
Jason is acting for the Duke of Sussex in judicial review claim concerning the arrangements for the provision of State security (with Shaheed Fatima KC).
Jason is acting the Ministry of Justice in Supreme Court in an appeal relating to changes to custodial terms of imprisonment for prisoners convicted of terrorist related offences (with Sir James Eadie KC).
Jason acting for the Claimants in challenge to wait times for access to treatment for gender identity development services for children and gender identity disorder services for adults.
Jason is regularly instructed by the BBC on an unled basis to provide advice on media, regulatory, freedom of information, and public law issues. This include issues arising under the BBC Charter, the Framework Agreement, the Broadcasting Code, the Communications Act 2003, and the Political Parties, Elections and Referendums Act 2000. He has also advised in respect of consultations and investigations, including the over-75 licence fee consultation, the gender disparity consultation, and the investigation by Lord Dyson into the Princess Diana interview.
Jason acted successfully for the Foreign Office in Divisional Court and Court of Appeal in case concerning the question as to whether certain provisions of the Diplomatic Privileges Act 1964 and the Vienna Convention on Diplomatic Relations 1961 are incompatible with Article 3 of the ECHR (with Sir James Eadie KC).
Jason is acting for the Foreign Office defending two habeas corpus applications brought by two British citizens currently located in North-East Syria (with Sir James Eadie KC).
Jason acted for the Motor Insurers’ Bureau and dozens of insurers in challenge to Secretary of State’s failure to properly implement the Motor Insurance Directive. The claim resulted in the passage of the Motor Vehicles (Compulsory Insurance) Act 2022 (with Tom de La Mare KC).
Jason acted successfully for Claimant refugee in a successful claim challenging the Secretary of State’s operation of a blanket policy to seize, retain and extract data from the mobile phones of migrants arriving by small boat ([2022] EWHC 695) (with Tom de La Mare KC).
Jason acted successfully for the Secretary of State for Justice in challenge to decision by the Parole Board which limited the temporal period over which the Parole Board can take into account risk to the public (with Sir James Eadie KC).
Jason acted successfully for the Prime Minister in high-profile challenge to decision to appoint Baroness Harding and other senior officials during the Covid-19 pandemic.
Jason acted for the Ruler of Dubai and Prime Minister of the UAE in respect of public law, human rights and public international law arguments in long-running family law proceedings. This involved multiple hearings in the Family Court, Divisional Court and Court of Appeal. These cases concerned foreign act of State; issues of diplomatic immunity and State immunity, and issues of procedural fairness.
Jason acted for Freedom From Torture in challenge to the UK Government’s refugee pushback policy on the basis that it was ultra vires, and incompatible with the 1951 Refugee Convention and Articles 3 and 4 ECHR. The Government withdrew the policy shortly before the hearing that was due to be heard before a Divisional Court in the week of 2 May, 2022.
Jason acted for ENRC in judicial review proceedings against the SFO regarding investigations into concerns of historical SFO wrongdoing, including in relation to legal professional privilege (with Mike Fordham KC, Hollie Higgins and Natasha Simonsen).
Jason acted for a number of interveners in this judicial review challenge where the Claimant seeks to challenge the legality of the Secretary of State’s decision to exclude most generators of onshore wind energy from participation in the third allocation round auction for the award of Contracts for Difference (with Kieron Beal KC).
Jason acted for the BBC in challenge brought by former BBC employee, Mr Keighley, challenging the framework that the BBC has in place to monitor compliance with its due impartiality obligations.
Jason acted for the Good Thinking Society in its judicial review challenge to the Professional Standards Authority over its decision to re-accredit the Society of Homeopaths, notwithstanding the fact that some of its practitioners continue to offer CEASE therapy (a purported treatment for autism which is targeted at children) (with Hollie Higgins).
Jason acted for the Law Society in its judicial review of cuts made by the Lord Chancellor to criminal legal aid, which resulted in the Divisional Court quashing the Lord Chancellor's decision on the grounds of unfairness and irrationality.
Jason acted for the Secretary of State for Justice defending judicial review claim alleging that the Parole Board lacks the requisite degree of independence, following the John Worboys challenge and subsequent resignation of the Parole Board Chair.
Represented Fair Vote Project in this high-profile claim challenging the Prime Minister's refusal to set up an inquiry to investigate irregular and unlawful conduct that sought to influence the outcome of the EU Referendum.
Jason acted for the Secretary of State for Justice in the Supreme Court, defending claim brought by a prisoner alleging that his extended determinate sentence, which mandates that he cannot be released until he is two-thirds of the custodial term, infringes Article 14 ECHR (with Sir James Eadie KC).
Jason acted for four prisoners (including one transgender prisoner) challenging strip searches that were carried out at HMP Peterborough. Sodexo conceded that the searches were unlawful. The claimants also alleged that the systemic problems in respect of supervision of strip searching constitutes a violation of the SSJ's positive obligations under Articles 3 and 8 ECHR.
Jason is also representing a number of prisoners at other prisons throughout the United Kingdom, that have been subject to similar strip searches.
Jason acted for the National Iranian Tanker Company in an urgent judicial review permission application, including an application for interim relief, relating to the SSHD’s decision to vote in favour of the redesignation of NITC. Permission for judicial review granted (with Tom de la Mare KC).
Jason advised for an environmental NGO in respect of a challenge to the decision of the Ministry of Defence to refuse to designate the Goodwin Sands as an archaeological site in light of the very large number of ships and planes that went down in this area during WWII. The issue has arisen as a result of a dredging application that has been made to build a port in Devon. The dredging will have detrimental impact on marine wildlife and the large number of ships, aircraft and crew lost at sea during WWII, during the Battle of Britain.
Represented BID and Medical Justice in case concerning immigration detention of those with mental illness (with Michael Fordham QC).
Represented Imperial Tobacco in its challenge to the Standardised Packaging of Tobacco Products Regulations 2015, in the High Court and Court of Appeal. The case raised issues relating to the deprivation of property, freedom of movement, and EU intellectual property law. Appeal to the Court of Appeal pending (with Dinah Rose KC and Brian Kennelly KC).
Jason acted for Drax and Infinis in the High Court and Court of Appeal for renewable source energy generators in challenge to the withdrawal of tax relief with practical immediacy. It was alleged that the withdrawal violated applicable standards of EU law, including the principles of foreseeability and proportionality, and A1P1 ECHR. (with Michael Fordham KC).
Jason acted for an eminent surgeon from Singapore in the High Court and Court of Appeal in a challenge to disciplinary proceedings by the GMC following a finding of overcharging by the Singapore Medical Council (with Michael Fordham KC).
Jason acted for the FRC in this case which concerns a challenge brought by auditors to a decision of the Executive Counsel to the FRC to deliver a formal complaint against the claimants. The FRC was successful in the High Court and Court of Appeal (with Michael Fordham KC).
Jason acted for the Association of British Insurers in this Reference which concerned the legislative competence of the National Assembly for Wales to recover NHS charges from tortfeasors and the compatibility of such recoupment with Article 1 Protocol 1 (with Michael Fordham KC).
Jason acted for the Secretary of State for Justice in this high-profile challenge to the SSJ’s policy on the receipt of books in prison (with Brian Kennelly KC).
Jason acted for the Attorney General of Jersey and the States of Guernsey in this case which concerned the constitutional relationship between the Channel Islands and the United Kingdom (with Sir Jeffrey Jowell KC and Iain Steele).
Jason is regularly instructed by the BBC, led and unled, to provide advice on media, regulatory and public law issues. This include issues arising under the BBC Charter, the Framework Agreement, the Broadcasting Code, the Communications Act 2003, and the Political Parties, Elections and Referendums Act 2000. He has also advised in respect of consultations, including the over-75 licence fee consultation.
Jason acted for a number of unaccompanied minors challenging the significant and ongoing delay by the SSHD in determining the claimants' individual asylum claims, and the systemic delay by the SSHD in determining asylum claims of unaccompanied children more generally. Raises issues under domestic law, EU law and public international law (in particular, under the Convention on the Rights of the Child).
Jason acted for IGas in application for interim injunction restraining persons unknown from a range of unlawful activity against fracking operators.
Jason is recognised as a leading civil liberties and human rights junior. He was shortlisted for Human Rights and Public Law Junior of the Year in the Chambers UK Bar Awards 2022. His clients include individuals, companies, States, current and former Heads of State and Heads of Government, members of the Royal Family, UK Government Departments, international organisations and NGOs. He regularly acts in high-profile litigation both for and against the UK Government. Jason has particular expertise and experience in the cross-over between commercial and competition law and human rights law.
Jason’s practice is complemented by his academic experience, having taught and published widely in the areas of public law and human rights, public international law and immigration and refugee law.
In addition to publicly funded work, Jason undertakes substantial pro bono work. He has acted pro bono for UNHCR, the Office of the Children’s Commissioner, Bail for Immigration Detainees, Medical Justice, the AIRE Centre, ILGA-Europe, the Human Dignity Trust, the Equality Network and the International Commission of Jurists. He has previously been nominated for the Bar Pro Bono Unit Pro Bono Barrister of the Year.
Jason is a member of the Attorney General’s A Panel of Counsel, the Attorney General's PIL Panel of Counsel and the Equality and Human Rights Commission Panel of Counsel.
“Jason provides fantastically clear advice. His drafting is terrific. Jason is insightful, hard-working and collegiate.”
Legal 500, 2023
“An absolute king with a silk-like practice.”
Chambers and Partners, 2023
“Jason is incredibly intelligent, phenomenally thorough, and an accomplished all-rounder. I am in awe of the diversity of his practice.”
Chambers and Partners, 2023
“He has a very diverse practice, he is a very nice team player and he is phenomenally bright.”
Chambers and Partners, 2022
“Jason is super bright, an excellent strategist, and he gets to the heart of the detail.”
Chambers and Partners, 2022
“He has an extraordinary legal mind and is an unusually fluent and articulate advocate. He is also a very affable and supportive team player.”
Legal 500, 2022
“He is also a very affable and supportive team player.”
Legal 500, 2020
“He has an extraordinary legal mind and is an unusually fluent and articulate advocate.”
Legal 500, 2021
Jason is acting pro bono on behalf of Ukraine in an inter-state case before the ECtHR concerning the Ukrainian Government's allegations of “human rights violations committed by the Russian Federation in its military operations on the territory of Ukraine since 24 February 2022”.
Jason is acting for the 11 lead refugee claimants in challenge to the Secretary of State’s Rwanda removal policy. Jason was part of the team which secured interim relief from the European Court of Human Rights.
Jason is acting for Annington in its judicial review challenge to decisions of the Ministry of Defence relating to enfranchisement of service family accommodation (listed as one of the top 20 cases for 2023) (with Monica Carss-Frisk KC).
Jason is acting for the Law Society in its challenge to the UK Government’s failure to implement the findings of the Bellamy Review into legal aid (with Tom de la Mare KC).
Jason is acting the Ministry of Justice in Supreme Court in an appeal relating to changes to custodial terms of imprisonment for prisoners convicted of terrorist related offences (with Sir James Eadie KC).
Jason acted successfully for the Foreign Office in Divisional Court and Court of Appeal in case concerning the question as to whether certain provisions of the Diplomatic Privileges Act 1964 and the Vienna Convention on Diplomatic Relations 1961 are incompatible with Article 3 of the ECHR (with Sir James Eadie KC).
Jason is acting for the Foreign Office defending two habeas corpus applications brought by two British citizens currently located in North-East Syria (with Sir James Eadie KC).
Jason acted successfully for Claimant refugee in a successful claim challenging the Secretary of State’s operation of a blanket policy to seize, retain and extract data from the mobile phones of migrants arriving by small boat ([2022] EWHC 695) (with Tom de La Mare KC).
Jason is acting for the Getty Museum in challenging a decision of the Italian Court of Cassation regarding the return of The Bronze statute, on the basis that such return is contrary to A1P1.
Jason is acting unled for the United Kingdom in a series of challenges brought in the European Court of Human Rights by media organisations alleging a violation of Article 10 in respect of costs orders requiring those organisations to pay success fees to successful claimants.
Jason acted for Claimant NGO and several MPs in judicial review challenge to the failure to investigate allegations of Russia interference in UK democratic elections. Currently pending before the European Court of Human Rights.
Jason acted for Freedom From Torture in challenge to the UK Government’s refugee pushback policy on the basis that it was ultra vires, and incompatible with the 1951 Refugee Convention and Articles 3 and 4 ECHR. The Government withdrew the policy shortly before the hearing that was due to be heard before a Divisional Court in the week of 2 May, 2022.
Jason acted for a child claimant challenging the £1017 Home Office fee. That is charged to children to register as British citizens. The claimants allege that this has the effect of depriving children of a statutory right, is contrary to the child’s best interests and infringes Article 8.
Jason acted for the AIRE Centre which has intervened in the Supreme Court in this important appeal concerning (i) the extent to which decisions of the Competent Authority may be binding on a tribunal; and (ii) the scope of the protective and investigative duties under Article 4 ECHR.
Jason advised the Equality and Human Rights Commission in connection with its work monitoring the human rights and equality implications of the Grenfell Tower tragedy including, in particular, in relation to the right to life under Article 2 ECHR, the right to adequate and dignified housing, the right to non-discrimination and equality, and children’s rights under the Convention on the Rights of the Child.
Jason acted for RT in a challenge to Ofcom's decisions (i) finding that RT had breached its due impartiality obligations in respect of seven programmes relating primarily to the Syrian war and the Skripal poisoning; and (ii) imposing a fine of £200,000 pounds. RT alleges that the decisions are incompatible with Article 10 ECHR or, alternatively, that the due impartiality regime is itself incompatible with Article 10. The case was heard before a Divisional Court in late-2019 and judgment is pending.
Jason acted for six families of recognised refugees residing in the UK Sovereign Base Areas of Akrotiri and Dhekelia in Cyprus. They have been residing there since 1998. The claimants challenge the decision of the SSHD to refuse admission to the UK. The case raises a number of fundamental issues under public international law, including, in particular, whether the Refugee Convention applies to this British overseas territory. The claimants succeeded in the High Court, Court of Appeal and Supreme Court (with Raza Husain KC, Tom Hickman KC and Eddie Craven).
Jason acted for four prisoners (including one transgender prisoner) challenging strip searches that were carried out at HMP Peterborough. Sodexo conceded that the searches were unlawful. The claimants also alleged that the systemic problems in respect of supervision of strip searching constitutes a violation of the SSJ's positive obligations under Articles 3 and 8 ECHR.
Jason is also representing a number of prisoners at other prisons throughout the United Kingdom, that have been subject to similar strip searches.
Jason acted for the Secretary of State for Justice in the Supreme Court, defending claim brought by a prisoner alleging that his extended determinate sentence, which mandates that he cannot be released until he is two-thirds of the custodial term, infringes Article 14 ECHR (with Sir James Eadie KC).
Jason acted for the Secretary of State for Justice defending judicial review claim alleging that the Parole Board lacks the requisite degree of independence, following the John Worboys challenge and subsequent resignation of the Parole Board Chair.
Advising Save the Children on public international law issues arising out of alleged massacre of Rohingya children in Myanmar. This involved the preparation of a detailed advice on potential violations of the Convention on the Rights of the Child with Professor Guy Goodwin-Gill QC, which Jason subsequently presented on behalf of Save the Children at the UN Human Rights Council at its 38th session in July 2018.
Jason acted for a number of unaccompanied minors challenging the significant and ongoing delay by the SSHD in determining the claimants' individual asylum claims, and the systemic delay by the SSHD in determining asylum claims of unaccompanied children more generally. Raises issues under domestic law, EU law and public international law (in particular, under the Convention on the Rights of the Child).
Jason acted for the claimants in this important case before the European Court of Human Rights, following the decision of the Supreme Court in Keyu v Secretary of State. The case addresses whether there is a human rights obligation under ECHR and/or customary international law to undertake a further inquiry into the 1948 massacre during the Malayan Emergency (with Michael Fordham KC, Danny Friedman KC and Zach Douglas KC).
Jason acted for Ineos in application for interim injunction restraining persons unknown from a range of unlawful activity against fracking operators and their third party contractors. Ineos succeeded in obtaining the interim injunction before the High Court. The case raises issues relating to the scope of Articles 10 and 11 ECHR, the appropriateness of obtaining relief against persons unknown, the test for quia timet interim injunctions, and the scope of the various alleged torts/statutory offences. A Court of Appeal hearing is listed for early 2019.
Jason acted for IGas in application for interim injunction restraining persons unknown from a range of unlawful activity against fracking operators.
Jason acted for the claimant in this case challenging the UK’s policy in relation to rough sleeping in the Upper Tribunal. The UK had passed a policy which suggests that rough sleeping in an of itself constitutes an “abuse of rights” for the purposes of Article 35 of the Citizens Rights Directive. This raised issues concerning free movement rights under the TFEU.
Jason acted for the Equality Network in its intervention in the Supreme Court in this important case involving questions as to the rights of transgender people to have information about their gender history kept private. The Equality Network submitted detailed evidence and submissions addressing the true impact that data retention policies have on the day-to-day lives of transgender people.
Represented UNHCR pro bono in the Supreme Court in this case which concerns the circumstances in which Art 8 ECHR will be engaged by a decision to prosecute a refugee for the use of false documents. The case has far-reaching implications for refugees entering the United Kingdom (with Raza Husain KC and Paul Luckhurst).
Jason acted for a mother and son in this important appeal before the Court of Appeal which concerns the proper approach to the definition of persecutory harm under the Refugee Convention in cases involving children. The child in this case is a 5-year albino boy, who would face widespread societal discrimination if returned to Nigeria, including a risk of ritual killing. The Secretary of State conceded the appeal before the hearing.
Jason acted for the AIRE Centre in the Court of Appeal in this case which concerns the application of Art 8 ECHR to unaccompanied refugee children in the Calais “Jungle” (with Raza Husain KC).
Represented approximately 1,400 Iraqi claimants in a series of cases in the High Court and Court of Appeal which concern, inter alia, the jurisdictional reach of Art 1 ECHR and the scope of the investigative duties under Art 3 and Art 5 ECHR, and the investigative obligations under UNCAT and customary international law (with Michael Fordham QC, Danny Friedman QC and Dan Squires QC).
Represented BID and Medical Justice in case concerning immigration detention of those with mental illness (with Michael Fordham QC).
Jason acted for the Secretary of State for Justice before the Supreme Court in this case which concerned whether the CFA and ATE premium regime in place prior to the Jackson reforms is compatible with Article 6 and A1P1 ECHR. In addition to acting in this case in the Supreme Court, Jason is representing the United Kingdom in proceedings in the European Court of Human Rights (with Tom Weisselberg KC).
Jason acted for UNHCR in its intervention before the Court of Appeal in this case which concern the proper interpretation of Art 1F(b) of the Refugee Convention (with Michael Fordham QC and Samantha Knights).
Represented the Equality and Human Rights Commission in its intervention before the Supreme Court in this case which concerns the test for disability discrimination in the social housing context (with Monica Carss-Frisk KC).
Jason acted for the Association of British Insurers in this Reference which concerned the legislative competence of the National Assembly for Wales to recover NHS charges from tortfeasors and the compatibility of such recoupment with Article 1 Protocol 1 (with Michael Fordham KC).
Jason acted successfully for the Office of the Children’s Commissioner before the Upper Tribunal and Court of Appeal in this challenge to the SSHD’s refusal to return a 5-year old boy from Nigeria and his mentally ill mother on the basis that the SSHD did not adequate consider the child’s best interests. SSHD ordered to return to the family (with Monica Carrs-Frisk KC and Kate Gallafent KC).
Jason acted for ILGA-Europe, AIRE Centre and the International Commission of Jurists in this case which concerns questions about the scope of the positive obligations to undertake effective investigation in the context of hate crimes motivated in whole or in part by an individual’s real or imputed sexual orientation or gender identity.
Jason is a highly sought after senior junior in the competition law space. He is ranked as a leading competition junior in Chambers UK, Chambers Global and Legal 500. In 2019, Jason was shortlisted for EU and Competition Junior of the year in the Legal 500 awards. He is currently acting in several of the largest domestic competition cases being litigated in the United Kingdom: the Visa interchange litigation; the trucks cartel; and the “dieselgate” litigation. He has expertise in collective proceedings before the Competition Appeal Tribunal, having acted for both claimants and defendants in this area. Jason also has expertise in advising on CMA mergers and market investigations, having acted both for and against the CMA. He has also advised the Hong Kong Competition Commission in relation to its own investigations. Jason also has a particular interest and expertise in sport-related competition issues.
“He has impressed with his excellent client skills and lateral thinking”
Chambers and Partners, 2022
Jason has been acting for more than 7 years in all aspects of the Visa interchange litigation, before the CAT, Commercial Court, Court of Appeal and Supreme Court. He is currently instructed in the umbrella interchange proceedings, as well as in the CPO proceedings.
Jason is acting for Volkswagen AG in judicial review challenge against the CMA to the extraterritorial scope of the Competition Act 1998. VW succeeded at first instance, and the CMA has been granted permission to appeal (with Brian Kennelly KC).
Jason is acting for Volkswagen AG in group litigation proceedings, which raises a number of EU and competition law issues, including in respect of the Commission’s decision regarding emission levels (with Brian Kennelly KC).
Jason is acting for Scania in relation to UK litigation arising from the Commission's decisions relating to the alleged trucks cartel. Encompasses High Court and CAT proceedings, including prospective CPO proceedings. This is anticipated to be the largest competition litigation for 2019/2020 (with Brian Kennelly KC).
Jason is acting for a large construction company in respect of a CMA market investigation.
Jason acts for the Premier League in an arbitration brought by Newcastle United challenging the Premier League’s decision that if the proposed acquisition of the Club by a consortium led by the Public Investment Fund of the Kingdom of Saudi Arabia proceeds, the KSA would become a “Director” of the Club, such that it would fall to be assessed against the PL Owners and Directors Test.
Jason acted for the Premier League in the simultaneous additional competition law proceedings brought before the Competition Appeals Tribunal by the 100% owner of the Club, St James Holdings Ltd, in relation to the same Premier League decision (with Adam Lewis KC).
Jason has advised the Premier League on various rule changes, including in respect of competition law issues.
Jason has provided advice to the Hong Kong Competition Commission in relation to an ongoing market investigation.
Jason acted for the CMA in a large-scale investigation into adult dating websites. The investigation was focused on consumer protection issues under the Consumer Protection from Unfair Trading Regulations, the Consumer Contract Regulations and the Consumer Rights Act, which arose in the context of an online dating company that offered niche dating websites.
Jason has appeared in many of the leading EU law cases in both the EU and UK courts. Jason has appeared in more than 25 cases in the General Court and Court of Justice of the European Union, on issues concerning sanctions, freedom of information, financial regulation and freedom of movement. He has particular expertise in EU sanctions law (see separate entry below). Jason continues to practice in the General Court and Court of Justice via the Law Library in Ireland.
At the domestic level, Jason continues to act in many of the leading cases concerning the role of EU law in the UK post-Brexit. He has particular experience and expertise on the Withdrawal Act 2018.
Jason is acting for a large group of Mexican shareholders challenging the decisions of the Single Resolution Board and the European Commission to take resolution action in respect of Banco Popular in 2017. This action resulted in the sale of Banco Popular to Banco Santandar for 1 euro. This was the first time that a resolution action of the Single Resolution Board has been challenged before the European Courts, and has been selected as one of four lead tests cases. The grounds of challenge included a failure to respect the shareholders' due process rights, property rights, and right to effective judicial review, and a failure to comply with the Meroni non-delegation principles. Jason appeared before the General Court unled. He is currently appearing unled in an appeal before the Court of Justice.
Jason is acting for a large group of Mexican shareholders challenging the decision of the Single Resolution Board to refuse access to a range of documents, requested pursuant to Regulation No. 1049/2001, involving its decision to take resolution action in respect of Banco Popular in 2017.
Jason is acting unled for several journalists in challenge to the European Parliament’s decision to refuse to provide public access to documents relating to expenses of a Member of Parliament who had been found guilty of the crime of membership and leadership of a criminal organisation.
Jason is acting in a number of confidential arbitrations raising issues under EU sanctions law, and the extent to which domestic, EU and US sanctions may justify non-performance of contractual obligations.
Jason is acting for Volkswagen AG in threatened group litigation proceedings, which raises a number of EU and competition law issues, including in respect of the Commission’s decision regarding emission levels.
Jason acted for Volkswagen AG in successfully defending a summary judgment and strike-out application which concerned the interpretation and application of Directive 2007/46. The case raised a number of issues concerning the role of EU law in the UK post-Brexit.
Jason acted for the Motor Insurers’ Bureau and dozens of insurers in challenge to Secretary of State’s failure to properly implement the Motor Insurance Directive. The claim resulted in the passage of the Motor Vehicles (Compulsory Insurance) Act 2022 (with Tom de La Mare KC).
Jason acted for the Motor Insurers’ Bureau in Court of Appeal case concerning important judgment concerning the extent to which the Motor Insurers’ Bureau has an obligation under the Codified Motor Insurance Directive to provide compensation where there is an unidentified or uninsured vehicle (with Tom de La Mare KC).
Jason is acting for Scania in relation to UK litigation arising from the Commission's decisions relating to the alleged trucks cartel. Encompasses High Court and CAT proceedings, including prospective CPO proceedings. This is anticipated to be the largest competition litigation for 2019/2020 (with Brian Kennelly KC).
Jason has been acting for more than 7 years in all aspects of the Visa interchange litigation, before the CAT, Commercial Court, Court of Appeal and Supreme Court. He is currently instructed in the umbrella interchange proceedings, as well as in the CPO proceedings.
Jason acted for the successful defendant in this sanctions case which concerned the EU Blocking Statute.
Jason acted for the Iranian Ministry of Defence in dispute concerning the enforcement of two arbitration awards made following a dispute arising of out of contracts for the supply of Chieftain tanks and armoured vehicles to Iran in the 1970s. The arbitrators held that the UK owed the principal sum of 140 million pounds to the Iranian Ministry of Defence pursuant to those contracts (later revised down to 127 million pounds). The sums have not yet been paid as a result of the imposition of EU sanctions. A number of disputes have arisen, including in relation to the payment of interest during the period in which the sanctions have operated (with Dinah Rose KC).
Jason acted for a number of interveners in this judicial review challenge where the Claimant sought to challenge the legality of the Secretary of State’s decision to exclude most generators of onshore wind energy from participation in the third allocation round auction for the award of Contracts for Difference (with Kieron Beal KC).
Jason acted for two journalists in a challenge to the European Border and Coast Guard Agency's decision to refuse to disclose information regarding border patrol ships, requested pursuant to Regulation No. 1049/2001. Appeared before the General Court unled.
Jason acted for Drax and Infinis in the High Court and Court of Appeal for renewable source energy generators in challenge to the withdrawal of tax relief with practical immediacy. It was alleged that the withdrawal violated applicable standards of EU law, including the principles of foreseeability and proportionality, and A1P1 ECHR. (with Michael Fordham KC).
Jason acted for Imperial Tobacco in its challenge to the Standardised Packaging of Tobacco Products Regulations 2015, in the High Court and Court of Appeal. The case raised issues relating to the deprivation of property, freedom of movement, and EU intellectual property law. Appeal to the Court of Appeal pending (with Dinah Rose KC and Brian Kennelly KC).
Jason acted for Imperial Tobacco in its challenge to the EU’s Second Tobacco Products Directive (with Dinah Rose KC and Brian Kennelly KC).
Jason is fast becoming a leading senior junior in the sports law field, particularly in cases with a cross-over with public law, competition law and public international law. Since 2020, Jason has been instructed in some of the biggest pieces of sports litigation in the UK, including by the Premier League and English Football Association. A number of Jason’s cases are confidential and cannot be listed below.
Jason acts for the Premier League in an arbitration brought by Newcastle United challenging the Premier League’s decision that if the proposed acquisition of the Club by a consortium led by the Public Investment Fund of the Kingdom of Saudi Arabia proceeds, the KSA would become a “Director” of the Club, such that it would fall to be assessed against the PL Owners and Directors Test.
Jason acted for the Premier League in the simultaneous additional competition law proceedings brought before the Competition Appeals Tribunal by the 100% owner of the Club, St James Holdings Ltd, in relation to the same Premier League decision (with Adam Lewis KC).
Jason acted unled for high-profile football player in arbitration dispute with agent.
Jason has advised the Premier League on various rule changes, including in respect of competition law issues.
Jason is a leading junior in the public international law field. He is regularly instructed in domestic and international cases that raised public international law matters, particularly issues concerning State and diplomatic immunity, foreign act of State, the interpretation of international treaties, and international sanctions. He has undertaken extensive work before the UN bodies, including the UN Human Rights Council, the UN Human Rights Committee, and the various UN working groups and Special Rapporteurs. He is regularly instructed by the Foreign Office on public international law issues, and is a member of their Panel of Public International Law Counsel. He also regularly provides pro bono advice to a number of NGOs on public international law issues, including UINHCR, Save the Children, Reprieve, and Freedom from Torture and UNHCR.
Jason is acting for the Foreign Secretary in a challenge brought by a child, alleging that the Vienna Convention on Diplomatic Relations is incompatible with Article 3 ECHR on the basis it precludes intervention in the case of domestic child abuse. Jason succeeded in the Divisional Court, and permission has been granted to the Court of Appeal.
“Jason is superb. He must be the leading junior in the field of international sanctions. He is incredibly hard working and knowledgeable, while at the same time being very personable and engaging. He is a pleasure to work with and clients love him.”
Legal 500, 2023
“He's just extremely efficient, delivers a fantastic work product, and is a thoughtful and effective advocate.”
Chambers and Partners, 2023
“He has a huge intellect and is a great drafter of arguments in documents. He’s great to speak to about cases as well and talk through big ideas.”
Chambers and Partners, 2023
“His standout attributes are his unbelievable work ethic and his attention to detail. He's genuinely exceptional.”
Chambers and Partners, 2023
“Jason is the expert and go-to junior in public international law. He has the perfect mix of academic and practical litigation so he is the total package in this are which is hard to find, as many counsel are one or the other.”
Legal 500, 2022
“Jason is a very academic international human rights lawyer and an authority on children's rights.”
Chambers and Partners, 2021
“He has an extraordinary legal mind and is an unusually fluent and articulate advocate”
Legal 500, 2021
Jason is acting pro bono on behalf of Ukraine in an inter-state case before the ECtHR concerning the Ukrainian Government's allegations of “human rights violations committed by the Russian Federation in its military operations on the territory of Ukraine since 24 February 2022”.
Jason is acting for the former Prime Minister of Kazakhstan. Mr Massimov was arrested and detained by State forces on or around 5 January 2022. In a petition to the UN Working Group, it was alleged that Mr Massimov had been arbitrarily detained, on the basis that: (i) it was not possible for Kazakhstan to invoke any legal basis justifying Mr Massimov’s arrest and detention (a Category I violation); and (ii) the non-observance of the international norms of fair trial were of such gravity as to give his deprivation of liberty an arbitrary character (a Category III violation). In an Opinion published in late-2022, the UN Working Group upheld both complaints.
Jason is acting for the 11 lead refugee claimants in challenge to the Secretary of State’s Rwanda removal policy. Jason was part of the team which secured interim relief from the European Court of Human Rights.
Jason acted successfully for the Foreign Office in Divisional Court and Court of Appeal in case concerning the question as to whether certain provisions of the Diplomatic Privileges Act 1964 and the Vienna Convention on Diplomatic Relations 1961 are incompatible with Article 3 of the ECHR (with Sir James Eadie KC).
Jason is acting for the Foreign Office defending two habeas corpus applications brought by two British citizens currently located in North-East Syria (with Sir James Eadie KC).
Jason is acting for the Getty Museum in challenging a decision of the Italian Court of Cassation regarding the return of The Bronze statute, on the basis that such return is contrary to A1P1.
Jason is acting unled for the United Kingdom in a series of challenges brought in the European Court of Human Rights by media organisations alleging a violation of Article 10 in respect of costs orders requiring those organisations to pay success fees to successful claimants.
Jason acted for Claimant NGO and several MPs in judicial review challenge to the failure to investigate allegations of Russia interference in UK democratic elections. Currently pending before the European Court of Human Rights.
Jason acted for the Ruler of Dubai and Prime Minister of the UAE in respect of public law, human rights and public international law arguments in long-running family law proceedings. This involved multiple hearings in the Family Court, Divisional Court and Court of Appeal. These cases concerned foreign act of State; issues of diplomatic immunity and State immunity, and issues of procedural fairness.
Jason co-authored a 95-page page opinion on the compatibility of the Nationality and Borders Bill and international refugee law (for Freedom from Torture) (available here). The opinion was cited repeatedly during the debate on the Bill in the House of Lords.
Jason also co-authored a detailed opinion on Clause 9 of the Nationality and Borders Bill (which provided for the UK Government to withdraw citizenship without notice) (for the Good Law Project).
Jason acted for the Secretary of State for Justice in a challenge to solitary confinement of a child. The case concerned the extent to which the Court was bound by soft international law instruments.
Jason acted for the Foreign Secretary in the Supreme Court case concerning ownership of the Venezuelan Gold. The case concerned the effect of a statement issued by the UK government recognising Juan Guaido as interim President of Venezuela (with Sir James Eadie KC).
Jason acted for the Foreign Secretary in proceedings brought by the parents of Harry Dunn, challenging the Foreign Secretary’s position on diplomatic immunity. Mr Dunn’s parents argued that the Secretary of State was wrong to conclude that (as the US stated) Mrs Sacoolas had diplomatic immunity. They also contended that the Secretary of State unlawfully confirmed and/or advised the Police that Mrs Sacoolas enjoyed diplomatic immunity, and/or obstructed the Police investigation of Mr Dunn’s death. Finally, Mr Dunn’s parents contended that the Secretary of State breached Article 2 of the ECHR. The Divisional Court dismissed the claim on all grounds (with Sir James Eadie KC).
Jason regularly advises individuals, the Foreign & Commonwealth Office and other government bodies on issues relating to State and diplomatic immunity.
Jason advises the Foreign & Commonwealth Office on its liability under public international law for acts that took place in a former colony.
Jason acted for six families of recognised refugees residing in the UK Sovereign Base Areas of Akrotiri and Dhekelia in Cyprus. They have been residing there since 1998. The claimants challenge the decision of the SSHD to refuse admission to the UK. The case raises a number of fundamental issues under public international law, including, in particular, whether the Refugee Convention applies to this British overseas territory. The claimants succeeded in the High Court, Court of Appeal and Supreme Court (with Raza Husain KC, Tom Hickman KC and Eddie Craven).
Advising Save the Children on public international law issues arising out of alleged massacre of Rohingya children in Myanmar. This involved the preparation of a detailed advice on potential violations of the Convention on the Rights of the Child with Professor Guy Goodwin-Gill QC, which Jason subsequently presented on behalf of Save the Children at the UN Human Rights Council at its 38th session in July 2018.
Jason advised the Equality and Human Rights Commission in connection with its work monitoring the human rights and equality implications of the Grenfell Tower tragedy including, in particular, in relation to the right to life under Article 2 ECHR, the right to adequate and dignified housing, the right to non-discrimination and equality, and children’s rights under the Convention on the Rights of the Child.
Jason acted for the claimants in this important case before the European Court of Human Rights, following the decision of the Supreme Court in Keyu v Secretary of State. The case addresses whether there is a human rights obligation under ECHR and/or customary international law to undertake a further inquiry into the 1948 massacre during the Malayan Emergency (with Michael Fordham KC, Danny Friedman KC and Zach Douglas KC).
Jason acted for investment funds, owned by the Libyan Investment Authority, in 10-day trial, and subsequently a two-day appeal, in the Cayman Islands. The case raised a number of complex issues involving the interaction between the UN, EU, UK and Cayman sanctions regimes. The central issue was whether the dismissal of directors of the investment funds constituted a breach of those regimes (with Dinah Rose KC).
Jason acted for the sons of the former president of Egypt and their wives, in challenging the EU sanctions imposed on the basis of alleged crimes in Egypt, notwithstanding that no evidence has been supplied to the Council in relation to the wives, the Egyptian courts have dismissed the allegations related to the sons and their single conviction, which is nevertheless spent, as well as their ongoing proceedings, are marred by flagrant violations of Articles 6 & 7 ECHR (with Brian Kennelly KC).
Represented UNHCR pro bono in the Supreme Court in this case which concerns the circumstances in which Art 8 ECHR will be engaged by a decision to prosecute a refugee for the use of false documents. The case has far-reaching implications for refugees entering the United Kingdom (with Raza Husain KC and Paul Luckhurst).
Jason acted for the former president of Egypt in challenging the EU sanctions imposed on the basis of alleged crimes in Egypt, notwithstanding that the Egyptian courts have dismissed the allegations relating to him, and his single conviction, which is nevertheless spent, as well as their ongoing proceedings, is marred by flagrant violations of Articles 6 & 7 ECHR (with Brian Kennelly KC).
Jason is advising the former President of Ukraine, Viktor Yanukovych, and his son, in challenging the EU restrictive measures imposed on them (with Shaheed Fatima KC).
Represented approximately 1,400 Iraqi claimants in a series of cases in the High Court and Court of Appeal which concern, inter alia, the jurisdictional reach of Art 1 ECHR and the scope of the investigative duties under Art 3 and Art 5 ECHR, and the investigative obligations under UNCAT and customary international law (with Michael Fordham QC, Danny Friedman QC and Dan Squires QC).
Jason acted for UNHCR in its intervention before the Court of Appeal in this case which concern the proper interpretation of Art 1F(b) of the Refugee Convention (with Michael Fordham QC and Samantha Knights).
Jason advises on a complaint to the ILO (with Shaheed Fatima KC).
Jason acted for ILGA-Europe, AIRE Centre and the International Commission of Jurists in this case which concerns questions about the scope of the positive obligations to undertake effective investigation in the context of hate crimes motivated in whole or in part by an individual’s real or imputed sexual orientation or gender identity.
Jason advises on various provisions of the Constitution of the Universal Postal Union, the General Regulations of the Universal Postal Union and the Universal Postal Convention (with Shaheed Fatima KC).
Jason advises on the definition of “investment” in various Bilateral Investment Treaties, and Article 25 of the Convention on the Settlement of Investment Disputes between States and Nationals of Other States.
Jason acted for the Application in his Communication to the UN Human Rights Committee.
Urgent Communication to the UN Working Group on Arbitrary Detention in connection with the arbitrary detention of a group of men detained in Australia in connection with suspected terrorist activities.
Jason advised an Australian citizen facing the death penalty in an overseas jurisdiction.
Jason has particular expertise and interest in issues concerning State and diplomatic immunity. He has been instructed in many of the leading cases on these issues, and regularly advises the Foreign Office, and individuals (including current and former Heads of State and Heads of Government) on issues concerning State and diplomatic immunity. Many of the instructions are confidential. Reported cases are listed below.
Jason acted for the Ruler of Dubai and Prime Minister of the UAE in respect of public law, human rights and public international law arguments in long-running family law proceedings. This involved multiple hearings in the Family Court, Divisional Court and Court of Appeal. These cases concerned foreign act of State; issues of diplomatic immunity and State immunity, and issues of procedural fairness.
Jason acted successfully for the Foreign Office in Divisional Court and Court of Appeal in case concerning the question as to whether certain provisions of the Diplomatic Privileges Act 1964 and the Vienna Convention on Diplomatic Relations 1961 are incompatible with Article 3 of the ECHR (with Sir James Eadie KC).
Jason acted for the Foreign Secretary in proceedings brought by the parents of Harry Dunn, challenging the Foreign Secretary’s position on diplomatic immunity. Mr Dunn’s parents argued that the Secretary of State was wrong to conclude that (as the US stated) Mrs Sacoolas had diplomatic immunity. They also contended that the Secretary of State unlawfully confirmed and/or advised the Police that Mrs Sacoolas enjoyed diplomatic immunity, and/or obstructed the Police investigation of Mr Dunn’s death. Finally, Mr Dunn’s parents contended that the Secretary of State breached Article 2 of the ECHR. The Divisional Court dismissed the claim on all grounds (with Sir James Eadie KC).
Jason is recognised as a leading EU and UK lawyer in sanctions-related work. He is highly sought after for his expertise in challenging and advising on EU and UK domestic sanctions. In 2018 he was awarded the World ECR Young Sanctions Practitioner of the Year Award. He has represented more than twenty-five individuals and entities in more than twenty challenges to asset-freezing regimes before both the General Court of the EU and the Court of Justice. Jason’s sanctions-related work is complemented by his academic background in public international law.
Jason also regularly appears in sanctions-related challenges in domestic Courts, both in the UK and abroad. Jason has particular experience with the sanctions regimes for Russia, Belarus, Iran, Egypt, Syria, Ukraine and Libya, and regularly advises banks, corporates and individuals on compliance issues, including the implications of sanctions to commercial transactions.
Jason regularly advises the Foreign Office and the Department of Transport on sanctions-related issues, and appeared successfully on behalf of the Foreign Office in the first court challenge to a sanctions designation under the Sanctions and Anti-Money Laundering Act 2018.
“He knows sanctions law inside and out.”
Chambers and Partners, 2023
“Jason works incredibly hard and his drafting is incredible.”
Chambers and Partners, 2023
“Jason is first-class, extremely quick to respond as well as accurate.”
Chambers and Partners, 2023
“Jason is really user-friendly, straight into the issues and has sharp insights.”
Chambers and Partners, 2023
“He was delightful to deal with. Very intelligent, proactive and a great member of the team.”
Chambers and Partners, 2022
“First-class drafting and a real pleasure to work with.”
Chambers and Partners, 2021
“No doubt a future star.”
Chambers and Partners, 2021
Jason regularly advises companies and individuals in relation to compliance with the EU and UK sanctions regimes, particularly with regard to Russia, Belarus, Iran, Libya, Egypt, Syria and Ukraine. This includes advice on the impact of sanctions on commercial transactions, and on issues concerning ownership and control. Jason has provided extensive advice on the implications of the Sanctions and Anti-Money Laundering Act 2018, and the Regulations made pursuant to that primary legislation. Much of his work is confidential, and cannot be listed here.
Jason acted for the Foreign Office in the first court review challenge to a UK decision to sanction an individual pursuant to the Sanctions and Anti-Money Laundering Act 2018.
Jason is acting for Mikail Gutseriev in challenge to designation by Council of the European Union.
Jason is acting in a number of confidential arbitrations raising issues under EU sanctions law, and the extent to which domestic, EU and US sanctions may justify non-performance of contractual obligations.
Jason acted for the successful defendant in this sanctions case which concerned the EU Blocking Statute.
Jason acted for the Iranian Ministry of Defence in dispute concerning the enforcement of two arbitration awards made following a dispute arising of out of contracts for the supply of Chieftain tanks and armoured vehicles to Iran in the 1970s. The arbitrators held that the UK owed the principal sum of 140 million pounds to the Iranian Ministry of Defence pursuant to those contracts (later revised down to 127 million pounds). The sums have not yet been paid as a result of the imposition of EU sanctions. A number of disputes have arisen, including in relation to the payment of interest during the period in which the sanctions have operated (with Dinah Rose KC).
Jason acted for the former president of Egypt in challenging the EU sanctions imposed on the basis of alleged crimes in Egypt, notwithstanding that the Egyptian courts have dismissed the allegations relating to him, and his single conviction, which is nevertheless spent, as well as their ongoing proceedings, is marred by flagrant violations of Articles 6 & 7 ECHR (with Brian Kennelly KC).
Jason acted for the sons of the former president of Egypt and their wives, in challenging the EU sanctions imposed on the basis of alleged crimes in Egypt, notwithstanding that no evidence has been supplied to the Council in relation to the wives, the Egyptian courts have dismissed the allegations related to the sons and their single conviction, which is nevertheless spent, as well as their ongoing proceedings, are marred by flagrant violations of Articles 6 & 7 ECHR (with Brian Kennelly KC).
Jason acted for investment funds, owned by the Libyan Investment Authority, in 10-day trial, and subsequently a two-day appeal, in the Cayman Islands. The case raised a number of complex issues involving the interaction between the UN, EU, UK and Cayman sanctions regimes. The central issue was whether the dismissal of directors of the investment funds constituted a breach of those regimes (with Dinah Rose KC).
Jason acted for the wife of the former president of Egypt in challenging EU sanctions imposed on the basis of alleged crimes in Egypt, notwithstanding that no evidence has been supplied to the Council (with Brian Kennelly KC).
Jason acted for the National Iranian Tanker Company before the General Court and Court of Justice in its application for interim relief and annulment in relation to its re-listing. The case concerns the reinstatement of sanctions on an entity in circumstances in which that entity has already won a legal challenge against a previous attempt to designate it, and the factual allegations against the Appellant have not changed. The issues before the Court raise fundamental questions about the need for effective remedies for unlawful action by the Council, and as to the proper limits on the Council’s ability to engage in unfair and abusive re-designation and re-litigation. An appeal is currently pending before the Court of Justice (with Tom de la Mare KC and Maya Lester KC).
Jason acted for the former Chief of Staff of the former Ukrainian President in challenging EU sanctions alleging misappropriation and corruption, on the grounds of breach of human rights and lack of evidence. In 2018, Jason appeared unled in the General Court, and succeeded in obtaining the annulling the freezing of funds for Mr Klyuyev for the period March 2017-March 2018, on the basis that the Council had committed a manifest error of assessment in determining that there was a legitimate basis for listing him. Jason is currently acting for Mr Klyuyev in relation to his re-designation (with Brian Kennelly KC).
Jason acted for Mr Klyuyev, a former Ukrainian politican, in challenging EU sanctions on the basis of a lack of evidence. Mr Klyuyev succeeded in overturning his designation, and, following extensive representations to the Council, was de-listed in early 2018 (with Brian Kennelly KC).
Jason acted for Mr Ivanyuschenko, a prominent Ukranian businessman and former politician, in his annulment application. The Court held that the Council had committed a manifest error of assessment in determining that there was a legitimate basis for listing him, and he was subsequently de-listed by the Council (with Brian Kennelly KC).
Jason is advising the former President of Ukraine, Viktor Yanukovych, and his son, in challenging the EU restrictive measures imposed on them (with Shaheed Fatima KC).
Jason acted for a former Ukrainian Minister of Revenue and Duties in his challenge to EU sanctions, on the basis that the allegations made by the new administration are false and driven by the commercial interests of the new rulers in Ukraine (with Brian Kennelly KC).
Jason acted for Mr Ezz and his wives before the General Court in this third application to unfreeze their assets (with Brian Kennelly KC).
Jason acted for Mr Ezz and his wives in an appeal to the Court of Justice challenging a decision of the General Court refusing to annul restrictive measures freezing funds in the EU because of an alleged misappropriation of Egyptian State funds in connection with the Mubarak regime. The Ezz judgment is one of the leading cases in this area (with Brian Kennelly KC).
Jason acted for the National Iranian Tanker Company in an urgent judicial review permission application, including an application for interim relief, relating to the SSHD’s decision to vote in favour of the redesignation of NITC. Permission for judicial review granted (with Tom de la Mare KC).
Jason acted for Mr Kurchenko in an application to annul restrictive measures freezing funds in the EU because of an alleged misappropriation of Ukrainian State funds in connection with the Yanukovych regime (with Brian Kennelly KC).
Jason practices in all aspects of media and entertainment law, with particular expertise in issues relating to broadcasting regulation, privacy, free speech and data protection. He regularly advises the BBC on a range of media and public law issues. He has also acted for a number of foreign broadcasters and foreign regulators. He has particular expertise on issues relating to due impartiality and freedom of expression, having acted in a number of leading cases in this area.
“Jason is just superb. He has got an eyewatering work ethic.”
Chambers and Partners, 2023
“Jason takes a very collaborative and collegiate approach.”
Chambers and Partners, 2023
“Jason quickly masters complex and unique areas of law and produces clear and convincing written work.”
Chambers and Partners, 2023
“He is pragmatic and shrewd in the way he provides legal advice.”
Chambers and Partners, 2023
“Jason is highly analytical, commercial and hard-working. He has a detailed knowledge of the media regulatory sector.”
Chambers and Partners, 2023
Jason is acting unled for the BBC in judicial review to Ofcom’s decision not to investigate a due impartiality complaint made against Ofcom, relating to the BBC’s coverage of Brexit.
Jason was instructed (as sole counsel) for the BBC in relation to the inquiry into the Princess Diana interview, conducted by Lord Dyson.
Jason is regularly instructed by the BBC on an unled basis to provide advice on media, regulatory, freedom of information, and public law issues. This include issues arising under the BBC Charter, the Framework Agreement, the Broadcasting Code, the Communications Act 2003, and the Political Parties, Elections and Referendums Act 2000. He has also advised in respect of consultations and investigations, including the over-75 licence fee consultation, the gender disparity consultation, and the investigation by Lord Dyson into the Princess Diana interview.
Jason is acting for the Getty Museum in challenging a decision of the Italian Court of Cassation regarding the return of The Bronze statute, on the basis that such return is contrary to A1P1.
Jason is acting unled for the United Kingdom in a series of challenges brought in the European Court of Human Rights by media organisations alleging a violation of Article 10 in respect of costs orders requiring those organisations to pay success fees to successful claimants.
Jason is acting unled for several journalists in challenge to the European Parliament’s decision to refuse to provide public access to documents relating to expenses of a Member of Parliament who had been found guilty of the crime of membership and leadership of a criminal organisation.
Jason acted for the RT channel (Russian national broadcaster) in the Court of Appeal, challenging Ofcom’s decision that RT had breached impartiality obligations on the basis that that finding is contrary to Article 10 ECHR.
Jason acted for the Ministry of Justice in an appeal against a decision of the Information Commissioner’s Office refusing access to information relating to compensation awarded to family members of Timothy Evans, who was hanged in 1950 for the murder of his baby daughter, but was given a posthumous royal pardon in 1966.
Representing the BBC defending its decision not to release certain information.
Jason acted for a large group of Mexican shareholders challenging the decision of the Single Resolution Board to refuse access to a range of documents, requested pursuant to Regulation No. 1049/2001, involving its decision to take resolution action in respect of Banco Popular in 2017.
Jason acted for RT in a challenge to Ofcom's decisions (i) finding that RT had breached its due impartiality obligations in respect of seven programmes relating primarily to the Syrian war and the Skripal poisoning; and (ii) imposing a fine of £200,000 pounds. RT alleges that the decisions are incompatible with Article 10 ECHR or, alternatively, that the due impartiality regime is itself incompatible with Article 10. The case was heard before a Divisional Court in late-2019 and judgment is pending.
Jason acted for two journalists in a challenge to the European Border and Coast Guard Agency's decision to refuse to disclose information regarding border patrol ships, requested pursuant to Regulation No. 1049/2001. Appeared before the General Court unled.
Jason acted for the BBC in challenge brought by former BBC employee, Mr Keighley, challenging the framework that the BBC has in place to monitor compliance with its due impartiality obligations.
Jason is regularly instructed by the BBC, led and unled, to provide advice on media, regulatory and public law issues. This include issues arising under the BBC Charter, the Framework Agreement, the Broadcasting Code, the Communications Act 2003, and the Political Parties, Elections and Referendums Act 2000. He has also advised in respect of consultations, including the over-75 licence fee consultation.
Jason has considerable experience advising on issues relating of data protection, freedom of information and privacy. He is regularly instructed to advise on data protection and freedom of information issues under domestic law and EU law. He has experience in challenging and defending decisions to refuse disclosure under the Freedom of Information Act 2000 and, at the EU level, Regulation No. 1049/2001.
Jason acted successfully for Claimant refugee in a successful claim challenging the Secretary of State’s operation of a blanket policy to seize, retain and extract data from the mobile phones of migrants arriving by small boat ([2022] EWHC 695) (with Tom de La Mare KC).
Jason is acting unled for several journalists in challenge to the European Parliament’s decision to refuse to provide public access to documents relating to expenses of a Member of Parliament who had been found guilty of the crime of membership and leadership of a criminal organisation.
Jason acted for the Ministry of Justice in an appeal against a decision of the Information Commissioner’s Office refusing access to information relating to compensation awarded to family members of Timothy Evans, who was hanged in 1950 for the murder of his baby daughter, but was given a posthumous royal pardon in 1966.
Representing the BBC defending its decision not to release certain information.
Jason acted for a large group of Mexican shareholders challenging the decision of the Single Resolution Board to refuse access to a range of documents, requested pursuant to Regulation No. 1049/2001, involving its decision to take resolution action in respect of Banco Popular in 2017.
Jason acted for two journalists in a challenge to the European Border and Coast Guard Agency's decision to refuse to disclose information regarding border patrol ships, requested pursuant to Regulation No. 1049/2001. Appeared before the General Court unled.
Jason has an extensive immigration practice. He appears regularly in the Court of Appeal and Supreme Court in many of the leading refugee and migration cases. He is also widely regarded as one of the world’s leading academic experts on child refugees. His the author of the monograph published by Cambridge University Press, The Child in International Refugee Law; he is regularly invited to provide guest lectures on refugee issues, including annual lectures at Harvard University; he has designed and taught a course on child refugees at the University of Oxford; and he is currently co-authoring the next edition of the Law of Refugee Status with Professor James Hathaway and Michelle Foster.
He has appeared in many of the leading immigration and citizenship cases in recent years
“A really good barrister. He has an encyclopaedic knowledge of public, refugee and immigration law.”
Chambers and Partners, 2023
“He is a meticulous barrister and is diligent in his work.”
Chambers and Partners, 2022
“Jason is extremely clever, and can draw on both his litigation experience and his academic background to enormous advantage. He writes beautifully.”
Legal 500, 2022
“Excellent drafting skills, font of huge knowledge around child rights in particular.”
Legal 500, 2021
Jason is acting for the 11 lead refugee claimants in challenge to the Secretary of State’s Rwanda removal policy. Jason was part of the team which secured interim relief from the European Court of Human Rights.
Jason acted successfully for Claimant refugee in a successful claim challenging the Secretary of State’s operation of a blanket policy to seize, retain and extract data from the mobile phones of migrants arriving by small boat ([2022] EWHC 695) (with Tom de La Mare KC).
Jason acted for an unaccompanied minor, challenging the Government’s age-determination process.
Jason acted pro bono for Detention Action in appealing concerning the lawfulness of the Home Office’s fast track asylum scheme.
Jason acted for the UN Special Rapporteur in Court of Appeal and Supreme Court appeals which concerned whether it was lawful to cancel Ms Begum’s citizenship without access to an effective appeal.
Jason acted in the Supreme Court on behalf of the mother in the high-profile, and now leading Hague Convention child abduction case on the relationship between the Hague Convention and refugee law. Jason was brought into this case to deal with all immigration issues. He has since been instructed in another large and high-profile child abduction case involving a Russian family (again advising on all immigration issues in that case).
Jason co-authored a 95-page page opinion on the compatibility of the Nationality and Borders Bill and international refugee law (for Freedom from Torture) (available here). The opinion was cited repeatedly during the debate on the Bill in the House of Lords.
Jason also co-authored a detailed opinion on Clause 9 of the Nationality and Borders Bill (which provided for the UK Government to withdraw citizenship without notice) (for the Good Law Project).
Jason acted for Freedom From Torture in challenge to the UK Government’s refugee pushback policy on the basis that it was ultra vires, and incompatible with the 1951 Refugee Convention and Articles 3 and 4 ECHR. The Government withdrew the policy shortly before the hearing that was due to be heard before a Divisional Court in the week of 2 May, 2022.
Jason acted for Afghan national at risk of persecutory harm in Afghanistan on account of his political activity. The claimant was returned notwithstanding that risk, and is seeking an order compelling re-entry so that he can exercise his right to an in-country appeal.
Jason acted for a number of families in connection with involvement in scheme which provided a route to obtain Tier 1 (Investor) visas. The cases raise issues in relation to the Tier 1 (Investor) route, Article 8 ECHR, and Article 3 of the Convention on the Rights of the Child.
Jason acted for a child claimant challenging the £1017 Home Office fee. That is charged to children to register as British citizens. The claimants allege that this has the effect of depriving children of a statutory right, is contrary to the child’s best interests and infringes Article 8.
Jason acted for six families of recognised refugees residing in the UK Sovereign Base Areas of Akrotiri and Dhekelia in Cyprus. They have been residing there since 1998. The claimants challenge the decision of the SSHD to refuse admission to the UK. The case raises a number of fundamental issues under public international law, including, in particular, whether the Refugee Convention applies to this British overseas territory. The claimants succeeded in the High Court, Court of Appeal and Supreme Court (with Raza Husain KC, Tom Hickman KC and Eddie Craven).
Jason acted for the claimant in this case challenging the UK’s policy in relation to rough sleeping in the Upper Tribunal. The UK had passed a policy which suggests that rough sleeping in an of itself constitutes an “abuse of rights” for the purposes of Article 35 of the Citizens Rights Directive. This raised issues concerning free movement rights under the TFEU.
Jason acted for the AIRE Centre which has intervened in the Supreme Court in this important appeal concerning (i) the extent to which decisions of the Competent Authority may be binding on a tribunal; and (ii) the scope of the protective and investigative duties under Article 4 ECHR.
Jason acted for a number of unaccompanied minors challenging the significant and ongoing delay by the SSHD in determining the claimants' individual asylum claims, and the systemic delay by the SSHD in determining asylum claims of unaccompanied children more generally. Raises issues under domestic law, EU law and public international law (in particular, under the Convention on the Rights of the Child).
Represented UNHCR pro bono in the Supreme Court in this case which concerns the circumstances in which Art 8 ECHR will be engaged by a decision to prosecute a refugee for the use of false documents. The case has far-reaching implications for refugees entering the United Kingdom (with Raza Husain KC and Paul Luckhurst).
Jason acted for the AIRE Centre in the Court of Appeal in this case which concerns the application of Art 8 ECHR to unaccompanied refugee children in the Calais “Jungle” (with Raza Husain KC).
Represented BID and Medical Justice in case concerning immigration detention of those with mental illness (with Michael Fordham QC).
Jason acted successfully for the Office of the Children’s Commissioner before the Upper Tribunal and Court of Appeal in this challenge to the SSHD’s refusal to return a 5-year old boy from Nigeria and his mentally ill mother on the basis that the SSHD did not adequate consider the child’s best interests. SSHD ordered to return to the family (with Monica Carrs-Frisk KC and Kate Gallafent KC).
Jason acted for a mother and son in this important appeal before the Court of Appeal which concerns the proper approach to the definition of persecutory harm under the Refugee Convention in cases involving children. The child in this case is a 5-year albino boy, who would face widespread societal discrimination if returned to Nigeria, including a risk of ritual killing. The Secretary of State conceded the appeal before the hearing.
Jason has a particular interest and expertise in environment cases, particularly in the context of judicial review. He has particular expertise in cases with an EU law dimension.
“Very strategic and sharp, his written submissions are clear and concise and he skilfully steers cases drawing on his wealth of experience.”
Legal 500, 2023
“echnically very strong, commercially astute and a delight to work with, he is a go-to name for public law and environmental matters.”
Legal 500, 2022
“Extremely meticulous and client-friendly.”
Legal 500, 2021
Jason acted for a number of interveners in this judicial review challenge where the Claimant seeks to challenge the legality of the Secretary of State’s decision to exclude most generators of onshore wind energy from participation in the third allocation round auction for the award of Contracts for Difference (with Kieron Beal KC).
Jason advised for an environmental NGO in respect of a challenge to the decision of the Ministry of Defence to refuse to designate the Goodwin Sands as an archaeological site in light of the very large number of ships and planes that went down in this area during WWII. The issue has arisen as a result of a dredging application that has been made to build a port in Devon. The dredging will have detrimental impact on marine wildlife and the large number of ships, aircraft and crew lost at sea during WWII, during the Battle of Britain.
Jason acted for Drax and Infinis in the High Court and Court of Appeal for renewable source energy generators in challenge to the withdrawal of tax relief with practical immediacy. It was alleged that the withdrawal violated applicable standards of EU law, including the principles of foreseeability and proportionality, and A1P1 ECHR. (with Michael Fordham KC).
Jason acted for Ineos in application for interim injunction restraining persons unknown from a range of unlawful activity against fracking operators and their third party contractors. Ineos succeeded in obtaining the interim injunction before the High Court. The case raises issues relating to the scope of Articles 10 and 11 ECHR, the appropriateness of obtaining relief against persons unknown, the test for quia timet interim injunctions, and the scope of the various alleged torts/statutory offences. A Court of Appeal hearing is listed for early 2019.
Jason acted for IGas in application for interim injunction restraining persons unknown from a range of unlawful activity against fracking operators.
BA (University of Melbourne); LLM (University of Melbourne); BCL (Dist.) (Oxon) (Commonwealth Scholar); PhD (Cantab) (W.M. Tapp Scholar and Poynton Cambridge Australia Scholar)
The Child in International Refugee Law (Cambridge University Press, 2017), shortlisted for the triennial Inner Temple Book Prize (2018).
Jason has undertaken postgraduate study at the University of Melbourne, University of Oxford, University of Cambridge and New York University. He received his doctorate from the University of Cambridge for his thesis, “The Child In International Refugee Law”. His research has focused principally on public international law, public law and human rights, and international refugee law, and he has taught in these areas at the University of Cambridge, the University of Oxford, the University of London and New York University.
In 2010 Jason founded the Cambridge Pro Bono Project, which has, since its establishment, facilitated the involvement of hundreds of postgraduate students in various pro bono projects.
In 2011 Jason was a Visiting Fellow at New York University working under the supervision of Professor Philip Alston, where he was also involved in supervising students undertaking the International Human Rights Fellowship. In 2010 Jason was a Research Associate at Makerere University in Kampala, where he undertook research on unaccompanied refugee children, predominately from the Democratic Republic of the Congo.
Jason is presently a Research Associate at the Refugee Studies Centre at the University of Oxford.
Jason is regularly invited to speak and present at conferences and workshops both domestically and overseas, particularly on issues relating to human rights and international refugee law. He has recently delivered lectures in London, Oxford, Cambridge, Lund, Stockholm, Geneva and Boston. He has acted as a consultant to the Centre of Migration, Policy and Society at the University of Oxford, and the Diana, Princess of Wales Memorial Fund.
Jason is a trustee of the AIRE Centre.
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