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Chambers of Paul Brown QC and Rupert Warren QC.

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Gwion Lewis

Work 020 7430 1221
Landmark Chambers (Chambers of Paul Brown QC and Rupert Warren QC.)


Gwion Lewis specialises in public, planning, environmental, EU and public international law. He was "the most active barrister" at the junior Bar of England and Wales in 2016, measured by case days in the English courts (The Lawyer Court Rankings, 2016). Gwion is a member of the Attorney General's 'A' Panel of Junior Counsel, which means that he regularly acts for the UK Government in its most complex cases. He is also a member of the Welsh Government's 'A' Panel of Junior Counsel. To date, he has appeared in over 100 substantive judicial reviews and 120 public inquiries. Many of Gwion's cases feature aspects of planning and/or environmental law, but his interest in public law and judicial review extends more broadly to issues arising in immigration, human trafficking, education, equality and discrimination law, detention, transport, standards and ethics, care standards and property-related public law. Recent cases include: acting for a campaign group that submits that the UK has not made a valid "decision to withdraw" from the European Union under Art. 50(1) of the Lisbon Treaty; acting for the Home Office in various claims relating to the 'jungle' camp for asylum-seekers in Calais; successfully resisting the first claim brought in the UK alleging that the Secretary of State had breached her positive operational duty under Art. 4 ECHR in relation to an individual said to be at risk of human trafficking (R(TDT) v SSHD [2016] EWHC 1912 (Admin)); successfully challenging the decision to close a rural Welsh-medium primary school (R(Jones) v Denbighshire County Council [2016] EWHC 2074 (Admin)); acting for a coalition of 12 local authorities in the Parliamentary Select Committee hearings on HS2; advising Natural Resources Wales on various consent and permit applications relating to the proposed nuclear power station at Wylfa; acting as specialist counsel to the Planning Inspectorate ahead of the examination of plans to build a new runway at Heathrow Airport; obtaining planning permission on appeal for 24 high-end residential units in west London; acting for the Isle of Man Government in a public examination of a plan to allow over 5,000 new homes to be built on the island; acting for the Secretary of State in the leading authority on the correct approach to the presumption in favour of sustainable development in paragraph 14, NPPF (East Staffordshire BC v Secretary of State for Communities and Local Government [2017] EWCA Civ 893); successfully defending the first decision to grant planning permission for hydraulic fracking in the UK (R(Friends of the Earth) v North Yorkshire County Council [2016] EWHC 3303 (Admin)); successfully challenging a certificate of lawful development granted for a basement extension in London (Eatherley v Camden LBC [2016] EWHC 3108); resisting a challenge brought on A1P1 ECHR grounds to decisions to set low catch allocations for salmon fishing in the River Wye for conservation reasons (R(Mott) v Environment Agency [2016] EWCA Civ 564, on appeal to the Supreme Court); successfully challenging NS&I's decision to revoke its Welsh language scheme (R(Welsh Language Commissioner) v National Savings and Investments [2014] EWHC 488 (Admin)). Gwion is the editor of the ‘Wales’ section of the Planning Encyclopedia and he speaks regularly about legal affairs on television and radio. In 2013, he received the BAFTA Wales award for ‘Best Breakthrough’ for his television work. Recent broadcasting work includes writing and presenting critically-acclaimed documentaries on Brexit and the future of public service broadcasting for BBC Radio Cymru, and two series of Siarad o Brofiad (‘Speaking from Experience’) in which Gwion interviews prominent figures in Welsh public life on television for S4C. In 2017, he was made an Honorary Fellow of Bangor University for services to law.


Called 2005; Gray’s Inn. Broadcaster, television (S4C) and radio (BBC Radio Cymru) (2010-ongoing).


Welsh, French, Italian


Attorney General’s A Panel of Junior Counsel; Welsh Government's 'A' Panel of Junior Counsel; Legal Member, Welsh Government's Welsh Language Partnership Council.


Scholar, Jesus College, Oxford (BA (Hons), Jurisprudence; BCL (First Class)); New York University (LLM, specialising in international human rights, language rights and the interface between law and security); US-UK Fulbright Scholar (2003-2004); Visiting Scholar, European University Institute, Florence (2004); Honorary Fellow, Bangor University (2017).



London Bar

Administrative and public law (including local government)

Within: Administrative and public law (including local government) – Leading juniors

Gwion Lewis - Landmark ChambersHe presented his case effectively and attractively and has a real presence.

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Within: Environment – Leading juniors

Gwion Lewis - Landmark ChambersHas a particular gift in dealing with highly technical evidence and multi-faceted or particularly complex matters.

Within: Environment

Landmark Chambers is a ‘very well-rounded set, with a range of counsel for every issue and good availability of alternatives.’ In the Supreme Court, Neil Cameron QC acted for the local authority in Dover District Council v CPRE (Kent) regarding duties to give reasons, while James Maurici QC and Gwion Lewis appeared for the Environment Agency in R (Mott) v Environment Agency on whether fishermen should be compensated from public funds if their fishing rights are restricted in the public interest to avoid ecological damage.

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Within: Planning – Leading juniors

Gwion Lewis - Landmark ChambersAn excellent junior with notable reputation for matters involving a Welsh law dimension.

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