UK Government’s Supreme Court Champion – The ‘Treasury Devil’

For Sir James Eadie KC, Britain’s Supreme Court could well provide a sleeping arrangement for one of Britain’s outstanding, leading Silks, whose near-standard appearances in the highest court in the country are countless. James Eadie is both Whitehall’s secret weapon in constitutional battles and a barrister whose briefs span an A-to-Z bewildering breadth.

He is the lawyer appearing for the UK government when it faces its toughest legal battles, testing constitutional limits and dominating headlines.

As First Treasury Counsel (Common Law) since January 2009, Sir James Eadie holds what many consider the most prestigious brief at the English Bar. Known colloquially as the “Treasury Devil,” he’s the senior outside advocate the Crown turns to first when the stakes are highest.

His case list reads like a greatest hits of modern British public law. Consider them – Brexit’s Article 50 litigation, the prorogation crisis, the Rwanda deportation scheme, and countless national security challenges that never make the papers.

But he makes the law review rankings like Chambers with predictable regularity.

The Numbers Don’t Lie

Since 2015, The Lawyer’s Litigation Tracker has consistently ranked Eadie as the top barrister by court appearances, a remarkable achievement that speaks to both his stamina and his standing.

Legal directories place him in the first tier for public law and human rights work, with peers describing him as “phenomenal” and “the government’s go-to” for appellate advocacy.

Based at Blackstone Chambers, London’s premier public law set, Eadie operates at the intersection of constitutional law, politics, and national interest, a uniquely pressurized space where legal arguments carry diplomatic, security, and political consequences far beyond the courtroom.

From Cambridge to Constitutional Law

James Eadie’s path to the top began conventionally enough. He read law at Magdalene College, Cambridge, and was called to the Bar by Middle Temple in 1984. He took silk in 2008, and within a year made history by becoming the first QC to be appointed directly to the role of First Treasury Counsel, breaking with the traditional progression through junior Treasury Counsel positions.

His appointment to Blackstone Chambers in 2003 placed him alongside some of the UK’s finest public lawyers. But what distinguishes Eadie isn’t just his institutional pedigree, but rather the extraordinary breadth of his practice and his ability to master complex, fast-moving briefs that span multiple legal disciplines.

The Cases That Defined a Generation

Brexit’s Constitutional Earthquake

When Gina Miller challenged the government’s authority to trigger Article 50 without parliamentary approval, Eadie led for the government in what became the Miller v Secretary of State for Exiting the European Union case, one of the most significant constitutional cases in modern British history.

Though the government lost that particular battle, Eadie’s advocacy demonstrated his ability to construct sophisticated arguments on uncharted constitutional terrain.

He returned to the Supreme Court in the even more explosive Miller/Cherry prorogation case in 2019, when Boris Johnson’s decision to suspend Parliament was ruled unlawful. These weren’t just legal arguments, they were real-time constitutional engineering under intense political and media scrutiny.

The Rwanda Litigation

More recently, Eadie fronted the government’s defense of its controversial Rwanda asylum removals policy through multiple appellate stages, culminating in the Supreme Court’s 2023 ruling that the scheme was unlawful.

In an era when government lawyers face unprecedented challenges, Brexit’s constitutional upheaval, pandemic emergency measures, security threats in the digital age, and increasingly sophisticated legal challenges from well-funded campaign groups, Eadie has become the steady hand at the tiller.

The case showed his ability to navigate the intersection of immigration law, international treaties, human rights obligations, and domestic policy, all under the intense gaze of media attention.

National Security and Human Rights

Eadie’s practice extends deep into national security work, including regular appearances before the European Court of Human Rights.

Unlike many public law specialists who keep within their narrow lane of speciality interest, Eadie works the Whitehall waterfront handling everything from immigration and taxation to data protection and environmental law. His chambers describe a practice that ranges “from terrorism to tax,” with repeated appearances in both the UK Supreme Court and the European Court of Human Rights as senior advocate for the Crown.

And much, much more.

Modern constitutional cases rarely present single-issue questions. The Rwanda litigation, for instance, involved immigration law, treaty obligations, human rights, judicial review principles, and separation of powers arguments.

Brexit involved EU law, constitutional conventions, prerogative powers, and devolution questions.

His ability to see around corners, to spot the indirect tax implication in a constitutional argument, or the risk in a domestic policy, makes him invaluable when the government needs genuinely joined-up legal strategy.

Thus he can be defending the UK’s intelligence agencies’ ability to handle bulk interception; the Artice 8 notification requirements in tabloid journalism (Max Mosley v. UK); the prisoner voting litigation (Hirst v. UK) and countless challenges to the UK’s counter-terrorism measures.

High-Stakes Public Law

Eadie’s caseload clearly reveals a stunning array of different litigation, including the citizenship deprivation case involving Shamima Begum (pictured) the former schoolgirl who joined ISIS, the high-stakes case involving control of Venezuela’s gold reserves, repeated battles with activist litigation group the Good Law Project over the pandemic response and other issues and questions about corporate criminality and the disclosure of overseas documents in the KBR v. SFO case.

His ability to handle all-comers in the public law sphere with a unique ability and intellect that permits him to bring his expertise and advocacy skils to bear without fear or favour.

He’s also a fixture at major public inquiries, representing security agencies at the Leveson Inquiry into press ethics, the Manchester Arena bombing inquiry, and the London Bridge attack inquiry.

A Style Built for the Supreme Court

Those who have observed or worked alongside James Eadie point to a distinctive advocacy style perfectly calibrated for appellate courts.

“He’s calm, highly structured, and relentlessly on-point,” one Chambers profile notes. “He takes a judge with him by making the complex sound almost inevitable.”

There’s no courtroom pyrotechnics, no theatrical flourishes, rather rigorous analysis, marshaled facts, and well assembled arguments that are also well calibrated to the makeup of the Supreme Court, his Court of choice. In constitutional litigation his low-key authority is devastatingly effective.

His political and legal nous see him handled appellate litigation with restraint and precision, anticipting diplomatic, human rights and other issues, that can provide Judges with a principled path to the result the government needs, calibrated to also suit the Judges he argues before.

Despite his prominence, Eadie maintains a relatively low public profile. He’s a Bencher of Middle Temple, a mark of distinction within the profession.

Sir James Eadie’s public work transcends any particular case or government. Constitutional cases set precedents that last decades, shaping how power is operated. He is one law star who is helping write the case law that will govern the UK for generations, one Supreme Court hearing at a time.

For more profiles of the UK’s leading legal minds, visit LawFuel.com‘s Law Stars series.