This blog was written and researched by Dr. Nathan Tamblyn, Library Volunteer. 

This book, more commonly known simply as Erskine May, is the authoritative reference source for the conventions which govern Parliament. The DEI holds a first edition.

Conventions are rules which are not laws properly so called – they cannot be enforced in the courts – but they are nevertheless considered binding by those subject to them. Parliamentary conventions range from calling each other by titles or constituencies rather than by names, through to the details of who gets to say what and when in the scrutiny of proposed new laws.

The conventions described in Erskine May are important because they are followed by Parliament when legislating. In this way, they can be considered part of the British constitution. The British constitution is not written down in a single document, as is the case in some other countries. Rather, it consists of rules which derive from various sources, some written down in different places, and some evidenced by practice. Supporters of the British approach to constitutional law might point to its flexibility and adaptability; detractors might say that it lacks the clarity and certainty needed to constrain those with power.

Erskine May represents a pragmatic compromise. The book describes Parliamentary conventions, and so to that extent provides clarity about the rules to be followed. Meanwhile, the fact that the book has passed through multiple editions shows that conventions can evolve over time. Such an approach to legislative procedure aligns with the English common law method of deciding cases in the courts: past outcomes are considered binding, at least as far as they go, until new circumstances require the rule to be modified, or occasionally re-written.

Thomas Erskine May was born in 1815. He published his Treatise when he was 29 years old, describing himself as a barrister at law and assistant librarian of the House of Commons. He had begun working at Parliament when he was 16, and was called to the bar by Middle Temple when he was 23. This did not require him to practice law in the courts. Rather, membership of the Inns of Court could also be akin to joining a society of arts and letters.

The Treatise was first published by Charles Knight & Co., then of Ludgate Street (now called Ludgate Hill). Charles Knight himself also worked with the Society for the Diffusion of Useful Knowledge (1826-1846). The society had a national committee and regional committees, including a regional committee in Exeter. The society produced inexpensive publications for the education of the general public. This included the Penny Magazine – price 4s 6d for a nine-month subscription. The magazine contained an eclectic mix of general knowledge: for example, the first edition includes short entries on the ‘Antiquity of Beer’, ‘Fair Play’, and a ‘Description of Poland’ – and Knight often wrote content. The DEI holds original editions of the Penny Magazine (Classmark: Q 11.13).

Was Erskine May ‘useful knowledge’ to members of the DEI? A handwritten note inside the front cover records that the book was ‘Presented by a Visitor’ in 1847. Another note inside the back cover, perhaps in another hand, says ‘T S Duncombe arrested Sept 2. See Times of Sept 8/47’. In 1847, Thomas Slingsby Duncombe was MP for Finsbury (then a constituency in London). He was a popular figure, and his politics were progressive and liberal – but he was also a gambler who racked up debt. When his creditors arrested him, he invoked Parliamentary privilege to secure his freedom. Perhaps a member of the DEI turned to Erskine May to explore the extent of the asserted privilege. Perhaps they too were a creditor.

The Times newspaper reported on the Duncombe affair, which eventually made it before the courts (then located at Westminster Hall, but soon rehoused in the Royal Courts of Justice). In Goudy v Duncombe (1847), the court decided that MPs were privileged from arrest while Parliament was sitting, and for 40 days before and after. On that basis, Duncombe secured his release. The case itself was cited in subsequent editions of Erskine May when discussing Parliamentary privilege.

May produced nine editions of the Treatise, and retired as Clerk to the House of Commons, whereupon he was ennobled as Baron Farnborough (of Farnborough in Hampshire). He died six days later without heir, so the peerage became extinct, said to be the second shortest peerage in British history. Erskine May is now in its 25th edition and continues to be used in Parliament.

On a final note, it has been said that the principal institutions of the British constitution can be identified from the connected geography of London. Buckingham Palace is at one end of St James’s Park, at whose other end sits the Treasury and then the Houses of Parliament (and Westminster Hall). Parliament Street becomes Whitehall, with the civil service, and Downing Street off to the side. At Trafalgar Square, Whitehall connects with the Strand, with the Royal Courts of Justice and the Middle Temple at the far end. The Strand becomes Fleet Street, historically home of the press, which then becomes Ludgate Hill as it passes the Old Bailey and approaches St Paul’s Cathedral. Beyond is the commercial centre of the City of London.

Further reading:

Erskine May is available online for free on Parliament’s website. This includes a Preface which records the most recent innovations in Parliamentary procedure. Further information on May, Knight, and Duncombe can be found in the Oxford Dictionary of National Biography. Valerie Gray has also written a book on Knight (now published by Routledge). The archive of the Society for the Diffusion of Useful Knowledge is held by University College London. Oxford’s Very Short Introduction series contains a book on the British constitution (by Martin Loughlin), or visit the website of the Constitution Society. Goudy v Duncombe is reported at (1847) 1 Ex 430; 154 ER 183.