After years of breaking the rules, Boris Johnson must now hope his MPs won't change the only one keeping him in office

Britain has no single document which outlines what its democracy looks like. The British constitution is made up of huge amounts of legislation, all of which can be rewritten if needed, and rules and traditions which are widely accepted by all politicians.

This reliance on tradition and accepted standards works if everyone accepts them. When rules are broken, politicians resign, whether they are backbenchers, cabinet ministers or party leaders and prime ministers. Without this acceptance of gentlemanly (or gentlewomanly) standards, the parliamentary system would be unworkable and require more rigid standards.

For its supporters, this flexibility is one of the strengths of the UK's parliamentary system – everyone plays by the rules without needing them to be written down and argued over. It's a system that has served the UK well to date. The constitutional arrangements have bent when necessary – although critics would argue that this makes for an archaic system with only limited scope for meaningful change. But the system has survived and evolved over time. So what happens when the leader isn't playing by the rules? And what happens when they change them and the system has no way of challenging it?

That is the situation MPs currently find themselves in. In Boris Johnson they have a prime minister like no other. Previous leaders have been experts at bending – but not breaking – the rules to suit their purposes within the parliamentary system. The very purpose of a three-line whip is to make your party accept your policy and the whips have historically used every tool at their disposal to make rogue MPs toe the line.

There are legendary tales of the whips office. From Gavin Williamson's pet tarantula to the feared black books of past indiscretions, the whips were and are experts at persuading MPs to back their legislation.

But there are supposed to be some parliamentary rules. The Ministerial Code, for example, was supposed to set a minimum standard for behaviour in public life. And it came with the expectation that anyone found to be breaking it would be punished – and that they would accept their punishment, even if they didn't like it or agree with it.

Playing fast and loose

The proroguing of parliament in 2019 was the first clear indication that the Johnson government would not allow any awkward rules to get in the way of its plans. In late August 2019, Johnson advised the Queen to prorogue, or shut down, parliament for five weeks at the height of the Brexit crisis, to prevent MPs from blocking the government's deal for leaving the EU. This advice was later ruled to be as "unlawful" by the Supreme Court. This was just the first rule break with little or no punishment forthcoming.

In November 2021, backbench Conservative MP Owen Paterson was suspended from parliament for 30 days after being found to have lobbied for two companies he worked as an adviser for outside parliament – hardly the harshest of punishments. The government machine swung into action to force a vote on whether a new committee, packed with Tory MPs, should decide his fate and the future of the Standards Committee. This turned out to be one breach of the rules too far and, despite winning the parliamentary vote, the government agreed to new cross-party talks and another investigation into Paterson, causing him to resign his seat.

More rulebreaking followed, including the Partygate scandal. The prime minister has broken one rule after another and has refused to resign or even apologise in some instances. Individual words have been interpreted and reinterpreted again and again by backbenchers looking to offer some defence of their leader. But at what cost?

In some ways, there has been no cost at all. Johnson remains prime minister with an 80 seat majority.

But public trust in politicians in the UK is at the lowest level on record. Labour leads in many opinion polls and Johnson has just faced a vote of confidence in which 148 of his MPs voted against him.

Read more: Boris Johnson wins 'no-confidence' vote: but the margin will make him nervous

Hoist by his own petard

Ironically, the very thing Johnson keeps breaking could come to his rescue: the rules. The rules of the Conservative 1922 Committee of backbenchers make it clear that a leader can only face one confidence vote every 12 months – so, until June 2023, Johnson's position cannot be challenged via the 1922 committee. There has been much muttering that this rule could, however, be changed.

The chair of the 1922 Committee, Sir Graham Brady, does not appear to be in favour of changing the rules. But never say never. The Conservative party are excellent at recognising when a leader is an asset and, perhaps more importantly, when they are a lame duck.

They will eject any leader – no matter who they are – if they feel it benefits the party and its members. Margaret Thatcher discovered this when she asked her cabinet whether she should fight a second round during a leadership contest in 1990 after 11 years in government and 16 years as party leader.

But, while Johnson may be in an uncomfortable position, he is not in an unbearable one. While other prime ministers would almost certainly have resigned over many of these rule breaks, Johnson continues to cling to his position. He cannot be forced out by the Labour Party, nor currently the electorate – at least, not until the next election due in December 2024.

Until this election, only the Tory party can punish this rulebreaker in any meaningful way. While they may not do that today or tomorrow, they will not hesitate to sack him if they believe he has become an electoral disaster. Upcoming by-elections in Wakefield, Yorkshire and Tiverton and Honiton in Devon on June 23 might give many MPs cause to rethink their current charity towards their leader and rulebreaker-in-chief.

Victoria Honeyman does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.