19:51

That was Boris Johnson’s fourth main defeat in a Commons vote since he became prime minister. The other defeats were: on the Oliver Letwin motion allowing time for the Benn bill, on the Benn bill at second and third reading and on holding an early election. The final vote counted as a defeat, because Johnson did not get the required two-thirds majority, although technically he won, because more MPs voted in favour than against.

But what does this defeat mean?

Humble addresses are considered binding on the government. The passing of this motion (see 7.24pm) means the government is now obliged to release to the Commons:

1) all private messages sent between nine advisers, including Dominic Cummings, the prime minister’s de facto chief of staff, including text and WhatsApp messages and private emails, sent from 23 July relating to the prorogation of parliament.

2) all the documents prepared within government since 23 July 2019 relating to operation Yellowhammer and submitted to the cabinet or a cabinet committee.

The motion mentions 23 July because that is the day Boris Johnson became Tory leader. He become prime minister the following day.

The material is meant to be handed over by 11 September.

However, it does not seem likely that the government will comply. The Commons will not even be sitting on Wednesday. Michael Gove, the Cabinet Office minister, told MPs that he wanted to publish some version of the Operation Yellowhammer document anyway. But during the debate Geoffrey Cox, the attorney general, suggested that the government would not have the legal power to enforce the release of the internal prorogation messages, even if it wanted to comply. (See 5.51pm.)

Last year Labour used the humble address mechanism to require the publication of the attorney general’s legal advice about the withdrawal agreement. The government initially ignored the request, and it only complied a month later when MPs passed another motion finding the government in contempt of parliament.

In this case no such contempt motion will be passed any time soon, because after tonight the Commons will not be sitting until 14 October.

And even if it were passed, a contempt motion on its own would not necessarily force Boris Johnson’s government to comply. Theresa May’s government did, but May respected the authority of parliament. Johnson’s administration seems much more contemptuous of it.

On other issues MPs and campaigners have threatened legal action, or gone to court, to ensure that Johnson complies with their wishes. But this vote is not a matter of legislation, and it does not relate to the exercise of prerogative powers. It is a Commons procedural matter, and so it is hard to see on what basis the courts could intervene.

That’s all from me for the night. My colleague Mattha Busby is now taking over.