A Parliamentarian’s Guide to the Unwritten Constitution

2 June 2025

On Monday, 2 June, the Global Centre for Democratic Constitutionalism (GCDC), along with the House of Commons’ Parliament, Public Administration, and Constitution Hub; the Public Law Centre, University of Ottawa; and Durham Law School, organised a panel event titled ‘A Parliamentarian’s Guide to the Unwritten Constitution’.

The event began with a keynote address by Lord David Anderson of Ipswich, KBE KC (member of the House of Lords). In his speech, Lord Anderson discussed the evolving nature of constitutional principles and conventions, highlighting the importance of articulating these principles clearly. He pointed to David Torrance’s mapping exercise of the UK Constitution and the House of Lords Constitution Committee’s publication on legislative standards, expressing hope that these initiatives will serve as precursors to other similar exercises. Concluding his remarks, Lord Anderson proposed establishing a joint committee of both the House of Commons and the House of Lords, which would be the central body of reference for the political constitution.

Following the keynote speech, the first panel began, comprising Eve Samson (Clerk of the Journals), Andrew Makower (Clerk of Procedural Practice in the House of Lords), and Justin Leslie (Office of Speaker’s Counsel, Counsel for Domestic Legislation). The panellists provided insights into the internal workings of the Houses of Parliament, including Standing Orders and other rules of parliamentary procedure, the use of Statutory Instruments, the roles of MPs, and the relationships between the government and key institutions such as Parliament, the courts, and the devolved assemblies.

The second panel of the day presented a view from UK academia on the nature of constitutional norms and principles. Professor Jeff King (UCL Laws, GCDC) posited that norms become constitutional when they are authoritatively recognised by public officials within a society as being constitutional in character. Additionally, Professor Roger Masterman (Durham University) explained that while debates on constitutional rules and principles in the UK tend to be oppositional (law versus politics, courts versus the government), in reality there is no strict division between the two. Dr Hannah White (Institute for Government) agreed, adding that an ecosystem is at play, where a network of different institutions play roles in upholding and enforcing the principles of the Constitution. The speakers pointed to examples of such institutions and actors, including the courts, the Prime Minister, the Cabinet Secretary, MPs, and technocrats such as parliamentary staff and expert advisers.

The third panel drew on comparative experiences to enrich the discussions, exploring how unwritten constitutional norms and principles operate across different jurisdictions. Professor Vanessa MacDonnell (University of Ottawa) discussed the Canadian context, noting the absence of a cabinet manual that systematically outlines the conventions of cabinet government, which makes it more difficult for Parliament to hold the executive to account. Professor Colm O’Cinneide (UCL Laws, GCDC) examined the Irish model, where the Irish Supreme Court is empowered to enforce constitutional norms and principles but only intervenes in cases of ‘clear disregard’, giving considerable leeway to political branches. Professor Erin Delaney (UCL Laws, GCDC) turned to the US, where the brevity of the written Constitution leaves room for a multitude of unwritten norms, even if these norms may not be regarded locally as constitutional because they exist outside the constitutional text.

Following the substantive panels, a final plenary discussion at the end of the event touched on constitutional change and the evolution of constitutional principles. The discussion also emphasised the need to communicate the significance of constitutional principles not only to MPs but also to the wider public who hold the ultimate authority.

Lord David Anderson of Ipswich, KBE KC delivering the keynote address

Some participants at the event