Prorogation signals the end of a parliamentary session and brings nearly all parliamentary business – including most bills and all motions and parliamentary questions – to a close. MPs will only usually reconvene when a new parliamentary session, marked by the State Opening of Parliament and the Queen’s Speech, begins.
Parliament is usually prorogued during late April or early May, between each yearly parliamentary ‘session’ (unusually, however, the 2017 parliamentary session has spanned two years to allow time to pass the necessary legislation to prepare for leaving the EU).
Parliament may also be prorogued before it is ‘dissolved’ prior a general election, to wrap up parliamentary business early and allow MPs to focus on the election campaign.
MPs continue to hold their seats during prorogation – unlike dissolution – and continue to undertake constituency work.
Government ministers remain in place during prorogation, and civil servants are not subject to ‘purdah’ restrictions. Purdah is the period during which civil servants must exercise discretion about announcing any new or controversial government initiatives which could be seen to be advantageous to any candidates or parties in the forthcoming election. It is only when Parliament is dissolved that the ‘purdah’ rules apply.
Unlike the dissolution of Parliament, which is governed by the Fixed-term Parliaments Act, proroguing Parliament is a Royal Prerogative power exercisable by the Prime Minister. It does not require the consent of MPs.
Once Parliament is prorogued, most parliamentary business comes to an end and any unfinished business falls. However, since the 1998–99 parliamentary session, any government public bills introduced in the House of Commons which have not yet completed their last amending stage (usually report stage in the Commons) can survive prorogation and be ‘carried over’ into the next session. This prevents the need to re-introduce bills from scratch in the next session, saving parliamentary time. The decision to carry over bills is taken by the Government and must be agreed between the ‘usual channels’ (representatives of the main parties). Bills ‘carried over’ to the next session continue from the same stage reached in the preceding session.
Motions fall when Parliament is prorogued and, unlike public bills, cannot be carried over to the next session. No new bills or motions can be introduced once Parliament is prorogued.
Parliament has not been prorogued by a government as a means of circumventing parliamentary opposition to government policy since 1948, when Parliament was prorogued following the Lords' opposition to the Parliament Bill. The Government could only bypass the Lords after a delay of three sessions. By proroguing Parliament, the Government could hold a special short parliamentary session, thereby speeding up the process for overriding the Lords.
The Canadian Prime Minister prorogued the Canadian Parliament in 2008 in order to delay a vote of no confidence in the Government.
Given the parliamentary impasse over Brexit, some have argued that the Government should prorogue Parliament to allow it to proceed with a no deal Brexit without the threat of MPs passing legislation to try and prevent it. Such a move would be highly controversial.
If Parliament was prorogued to facilitate no deal, it would not be possible to pass any bills or remaining secondary legislation needed to prepare the UK statute book for such an outcome. It would also prevent the Government from legislating to change the ‘exit day’ currently legislated for in the EU Withdrawal Act and give effect to any new extension to Article 50.