MEET:
Barney McCay
"Barney is alarmingly bright and will go far. He is committed and works very hard until the job is done. He is my junior barrister of choice on all public law matters."
Chambers and Partners 2026
Barney practises in public law, environmental and planning law, and competition and regulatory law (including public procurement, subsidy control and commercial judicial review). He regularly acts in proceedings before the High Court, Court of Appeal and Supreme Court, and is ranked in both directories.
Barney has a broad public law practice and is on the EHRC’s panel of counsel.
Recent/current instructions include a challenge to the DWP’s use of AI, an appeal to the Supreme Court concerning the UK’s obligations under the Withdrawal Agreement, a challenge to the revocation of an OBE, an appeal concerning the application of the res judicata principle to public law proceedings, and an intervention before the Supreme Court concerning local authorities’ homelessness duties (acting for the NGO, Crisis).
Barney has considerable experience in public procurement, competition and subsidy aid matters. He acted for the Gambling Commission (led by Sarah Hannaford KC) in various challenges to its award of the national lottery licence, and was instructed in Motorola’s challenge to the UK emergency communication system procurement.
Barney is also currently acting in several subsidy control challenges (including a proposed challenge to a multi-billion-pound carbon capture scheme), and a trade dispute concerning the UK’s obligations under the WTO and TCA.
Barney has significant experience of private and public environmental claims. His recent instructions include challenges about badger culling, waste incineration, water pollution caused by intensive poultry farming, seal pup disturbance, and Defra’s policy on “fast growing chickens”.
Barney also has experience of group actions and successfully intervened on behalf of ClientEarth and Mums for Lungs in the “Dieselgate” proceedings.
Qualifications:
- Cambridge University – BA History and Politics (First Class).
- BPP University – Law Conversion (Distinction).
- City University – Bar Course (Outstanding).
- University of Pennsylvania – LLM (Distinction).
Awards:
- Fulbright Award (offered) for postgraduate study in the US.
- Thouron Fellowship for fully funded postgraduate study in the US.
- Bedingfield and Residential Scholarships from Gray’s Inn, its top awards for the BPTC.
- David Karmel Award from Gray’s Inn, its top award for the GDL.
- Postgraduate Scholarship from City University.
- Academic Scholarship from King’s College, Cambridge.
- Winner, Procurement Lawyers’ Association Essay Prize.
- Winner, Michael Beloff KC Essay Prize.
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"Barney is a very clear and very articulate advocate and he is able to deal with difficult opponents."
"Barney is alarmingly bright and will go far. He is committed and works very hard until the job is done. He is my junior barrister of choice on all public law matters."
"Barney pulls together strategic advice for multiple areas. He is willing to get all over the detail."
“Barney is amiable, intelligent, and diligent in his approach. His collaborative nature and sharp legal mind make him a strong asset to any case.”
“Barney is a stellar junior. His drafting is incredibly clear and concise. He has a clear perspective on the best and simplest way to achieve the client’s objectives.”
+44 (0)20 7404 3447
"Barney is alarmingly bright and will go far. He is committed and works very hard until the job is done. He is my junior barrister of choice on all public law matters."
Chambers and Partners 2026
MAIN AREAS OF PRACTICE
- Public Law
- Competition
- Environmental Law and Natural Resources
- Civil Liberties and Human Rights
Barney McCay
Contact Barney: barneymccay@matrixlaw.co.uk | +44 (0)20 7404 3447
Contact Barney's Practice Team (Team X): TeamX@matrixlaw.co.uk
Barney practises in public law, environmental and planning law, and competition and regulatory law (including public procurement, subsidy control and commercial judicial review). He regularly acts in proceedings before the High Court, Court of Appeal and Supreme Court, and is ranked in both directories.
Public Law (including Human Rights and Judicial Review)
Barney has a broad public law practice and is on the EHRC’s panel of counsel.
Recent/current instructions include a challenge to the DWP’s use of AI, an appeal to the Supreme Court concerning the UK’s obligations under the Withdrawal Agreement, a challenge to the revocation of an OBE, an appeal concerning the application of the res judicata principle to public law proceedings, and an intervention before the Supreme Court concerning local authorities’ homelessness duties (acting for the NGO, Crisis).
Competition Law (including Public Procurement and Subsidy Control)
Barney has considerable experience in public procurement, competition and subsidy aid matters. He acted for the Gambling Commission (led by Sarah Hannaford KC) in various challenges to its award of the national lottery licence, and was instructed in Motorola’s challenge to the UK emergency communication system procurement.
Barney is also currently acting in several subsidy control challenges (including a proposed challenge to a multi-billion-pound carbon capture scheme), and a trade dispute concerning the UK’s obligations under the WTO and TCA.
Environment and Planning
Barney has significant experience of private and public environmental claims. His recent instructions include challenges about badger culling, waste incineration, water pollution caused by intensive poultry farming, seal pup disturbance, and Defra’s policy on “fast growing chickens”.
Barney also has experience of group actions and successfully intervened on behalf of ClientEarth and Mums for Lungs in the “Dieselgate” proceedings.
Qualifications and Awards
Qualifications:
- Cambridge University – BA History and Politics (First Class).
- BPP University – Law Conversion (Distinction).
- City University – Bar Course (Outstanding).
- University of Pennsylvania – LLM (Distinction).
Awards:
- Fulbright Award (offered) for postgraduate study in the US.
- Thouron Fellowship for fully funded postgraduate study in the US.
- Bedingfield and Residential Scholarships from Gray’s Inn, its top awards for the BPTC.
- David Karmel Award from Gray’s Inn, its top award for the GDL.
- Postgraduate Scholarship from City University.
- Academic Scholarship from King’s College, Cambridge.
- Winner, Procurement Lawyers’ Association Essay Prize.
- Winner, Michael Beloff KC Essay Prize.
"Barney is a very clear and very articulate advocate and he is able to deal with difficult opponents."
"Barney is alarmingly bright and will go far. He is committed and works very hard until the job is done. He is my junior barrister of choice on all public law matters."
"Barney pulls together strategic advice for multiple areas. He is willing to get all over the detail."
“Barney is amiable, intelligent, and diligent in his approach. His collaborative nature and sharp legal mind make him a strong asset to any case.”
“Barney is a stellar junior. His drafting is incredibly clear and concise. He has a clear perspective on the best and simplest way to achieve the client’s objectives.”