Why today’s partygate vote on inquiry into whether Boris Johnson lied to MPs matters

It is a challenging day to be a Tory MP. Because they are being ordered to turn up to the House of Commons to prevent their leader, the prime minister, being investigated to establish whether he lied to all MPs when saying there were no rule-breaking parties.

And they have been told to do this despite knowing the PM has important questions to answer, now that he has been fined by the police for attending a rule breaking party.

So if Tory MPs turn up to the Commons to speak in defence of the PM, what are they supposed to say that won’t be used against them in opposition parties’ election leaflets?

The PM hopes he has given them a respectable way to defend him, by amending Labour’s motion such that any vote to refer him for investigation by the Privileges Committee won’t happen till after the police have ended their investigations and till after Sue Gray’s report into the lawbreaking parties is published.

But Labour’s motion would explicitly delay the “substantive” work of the Privileges Committee till after the police had completed all their Partygate work.

So Keir Starmer will – with some force - describe the Tory amendment not as a delaying tactic but as a wrecking amendment, that wouldn’t just kick the can down the road but would boot it out of the park.

That puts Tory MPs on the spot. Because the whole point about Labour’s motion is not to prejudge whether the PM is guilty of lying to MPs but to initiate the constitutionally correct process to establish whether he lied.

Starmer will argue that any Tory MP voting against Labour’s motion is defending the indefensible. And that was in effect what the senior Tory MP, the former chief whip Andrew Mitchell, said on my show last night.

He said he won’t be voting today, in defiance of the prime minister’s three line whip. And his conviction is that enough of his colleagues will also bunk off parliament and abstain such that the opposition party’s motion will be passed, possibly even without the need for a formal vote.

We’ll see. But to be clear what is at stake here is different from and arguably as important as whether Boris Johnson should be forced out of office.

As I said last week, it is whether the conduct of a prime minister perceived to have broken important rules can be properly and transparently assessed by his peers - as you would expect if there were a functioning constitution in a first-past-the-post parliamentary democracy – when that PM benefits from a big Commons majority.

It is why - as I said - it is not hyperbole to describe this impasse as a constitutional crisis.

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