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On 12 July, Keir Starmer tabled a vote of no confidence in the government. Normally, time in Parliament will be found to vote on a confidence motion when proposed by the leader of the opposition. However, the government refused to allocate time for this vote as the motion also stated that the House had no confidence in the current Prime Minister. Instead, the government proposed its own vote of confidence in the government, which is likely to take place on 18 July.

This argument illustrates three important features of the UK constitution: the role of constitutional conventions; the role of political parties and the importance of time. It also shows how much the UK constitution relies on those in power being willing to follow conventions and standards of good constitutional behaviour– and the problems that arise when they are unwilling to play by the rules.


The UK is (in)famous for having an un-codified constitution. Whilst the UK does have legislation that deals with aspects of the constitution, e.g. the Human Rights Act 1998 and the devolution legislation, many of the rules are found in constitutional conventions. Constitutional conventions are not the same as law and courts do not enforce them.

Nonetheless, these conventions play an important role. For example, the convention that the government can only remain in power to the extent that it has the confidence of the House of Commons upholds democracy. It stops a government from trying to cling on to power when it is clear that it is not supported by MPs and, therefore, by the electorate who voted for those MPs.

However, many conventions are vague. Here, the constitutional convention is that the government will table a vote of no confidence when this is proposed by the leader of the opposition. The question is – what IS a vote of no confidence? Does it only include a specifically worded motion that ‘This House has no confidence in Her Majesty’s Government’, or does it also include so-called ‘censure motions’ expressing no confidence in key governmental policies, or in particular members of the government?

A motion that merely criticises the Prime Minister would not trigger the convention. The motion proposed by Keir Starmer focused on a lack of confidence in the government and the current Prime Minister. It was for the government to decide whether that motion was a vote of no confidence in the government as a whole, or a censure motion of the Prime Minister.

This vagueness shows how hard it can be to hold any government to account. Governments can argue that a convention has been either misunderstood or changed, rather than breached. This is even more problematic when the government alone can determine if a convention applies.

Role of political parties

The Conservative Party is now electing a new leader who will become the next Prime Minister. They will do so according to rules written by members of the Conservative Party.

This illustrates the importance of political parties in the UK constitution. Would Boris Johnson have felt the need to resign if he had not faced an earlier vote of no confidence in his leadership of the party, and then seen so many government MPs resign over concerns as to his leadership?

It also shows how the UK is a parliamentary democracy. The Monarch appoints a Prime Minister. By convention, she appoints the leader of the political party that enjoys the confidence of the House of Commons, normally because that political party has a majority of MPs. For all of the claims that a particular leader or Prime Minister has the mandate of the country, it is important to recognise that any Prime Minister was only voted for by the electorate living in their constituency. The rest of the ‘mandate’ is a vote for the policies of the political party of which the Prime Minister is the leader.

Yet, as the current leadership contest illustrates, different potential Prime Ministers have different policies. This means that the electorate can see policy changes occurring midway through a parliamentary term. Should a political party have so much control over the identity of a future Prime Minister and the timing of when a new Prime Minister will be appointed, especially when this may be a long time before there can be a general election to approve or reject these policy changes?

The importance of time

The government has a large degree of control over parliamentary time but the convention of allocating time for votes of no confidence interferes with governmental business, as well as potentially forcing a change of leader or a general election if the vote of no confidence succeeds.

There are means through which the House of Commons can ‘take back control’ – as happened in 2019 surrounding Brexit. However, these are rarely successful other than during a minority government. Without this control over time, the government may not be able to achieve its agenda. However, too much control over time may also mean that the opposition is not able to hold the government effectively to account for its actions. Getting the balance right is important, yet difficult to achieve.

Standards or politics?

The ins and outs of the vote of confidence debate show, again, that the UK has a predominantly political as opposed to legal constitution. This can be a good thing, especially when it upholds democracy. A combination of Parliament, the political party and the people were able to oust a Prime Minister, forcing his resignation due to his behaviour in office. It also maintains flexibility, enabling the rules to change quickly when needed.

However, it also illustrates a deeper potential weakness.  Conventions are meant to ensure that members of the government act in a way that upholds constitutional principles. But their vague nature and political enforcement mean they can also be used to ‘play politics’. Did Boris Johnson resign, for example, because he broke these constitutional principles, or because his party were concerned he would no longer win a general election and so found a way to force him to resign?

If we want to ensure our political constitution upholds good standards of constitutional government, we need to make sure MPs and the electorate know what these principles are, and believe in them enough to ensure they are upheld. If not, conventions may fail to uphold constitutional standards and, instead, just be a further means of shoring up political power.

By Alison Young, Sir David Williams Professor of Public Law at the University of Cambridge.


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