Rayner had no choice but to go, but her exit now puts Labour on fast track to civil war, writes Natasha Clark

Despite the political capital, Sir Keir Starmer was prepared to spend in a bid to save her, he had little choice but to cut her loose.

The Deputy Prime Minister was found to have acted "with integrity and with a dedicated and exemplary commitment to public service."

However, he said it was an “unfortunate failure” that she didn’t pay enough stamp duty.

Read more: Rayner resignation triggers major Cabinet reshuffle as Lammy named deputy PM and Cooper moves to Foreign Office

He concluded that "in relation to this matter, she cannot be considered to have met the “highest possible standards of proper conduct” as envisaged by the Code. Accordingly, it is with deep regret that I must advise you that in these circumstances, I consider the Code to have been breached."

So, not breaking the rules, per se, but being seen to have not done everything in power in order to do everything by the book.

Sir Keir, who made a huge case for cleaning up politics, needed to put his money where his mouth is, and he has.

It’s a huge moment for the Labour government after just a year in office.

And the loss of Labour’s main attack dog, Housing Secretary and Deputy Leader will have far-reaching ramifications for the future of British politics.

In the near term, it is the final job in that list which is going to be the trickiest for the Prime Minister to weather.

A Deputy leadership election at this point is just about the last thing that Sir Keir Starmer needs.

On Friday, Sir Keir attempted to stave off the critics by appointing David Lammy as Deputy Prime Minister.

Another person of the left in the Labour Party, Mr Lammy’s made a household name for himself by speaking out about the deteriorating situation in Gaza in recent weeks.

He will keep the left wing of the party in line while the leadership election takes place.

We may see big names like Louise Haigh, the former transport secretary, or Thangam Debbonaire seek to run for a comeback.

Sir Keir will be keen not to upset the political balance of his leadership team, and will want another Rayner-style figure to fill her boots.

But there will be eager young things, and those on the more moderate wings of the Labour movement who will also surely want to run.

It’s also unclear whether such a move would be expedited, or not.

A long, drawn-out contest of MPs fighting each other would further harm the PM’s promises to have turned the page on Tory chaos.

We’ll get the details of how, and when the contest will take place in the coming days.

The PM will have a shiny new reshuffled team of people to show off at the party conference, according to the reshuffle details that we have been hearing so far.

But as of yet, no big names going into government.

In fact, it’s a bit of a shuffle of the deckchairs, rather than any radical new moves.

Time will tell if this will be a safety-first approach for the PM, or a radical reboot to propel Labour back into orbit.