“I am in blood 

Stepp’d in so far that, should I wade no more, 

Returning were as tedious as go o’er.”

By his third Act, Macbeth at least acquired a sort of grim logic to justify his destructive behaviour – things could not be made any worse by stopping, he reasoned, so he was compelled to press on.

By contrast, the Government seems to have looked at its boots and decided the handling of the Raab amendment simply hadn’t made enough of a mess, so wading in a bit further in might be positively desirable.

Here’s the state of play after quite an extraordinary lunchtime:

  1. The Government payroll vote “in its widest sense” will abstain on the Raab amendment. (To appreciate the importance of the phrase “its widest sense”, see Paul’s post on the staggering expansion of patronage in the parliamentary party).
  2. Downing Street has let it be known that their reason for abstaining is that “they are sympathetic to the amendment’s aims but believe it to be non-compliant, eg not compatible with the law, and so are barred from voting for it by the ministerial code”.
  3. Theresa May made a statement which was roundly critical of the legality of Raab’s proposal, but refused to be drawn on the Government’s position – apparently unaware that everyone with a phone had already seen the news on Twitter.
  4. The Lib Dem payroll vote will be breaking with their coalition partners to vote against the amendment.
  5. Labour are yet to give an official statement of which way they will fall.

All in all, it’s quite the dog’s dinner.

Dom Raab is understandably pleased – he feels strongly about the principles at stake, and this is a big boost to his efforts. He told me:

“I welcome the government’s acquiescence in trying to pass these amendments. Backbenchers will have a real chance to deliver an important reform to protect the public.”

The impact of the decision will go beyond this policy, though.

On its simplest level this is an extension of the whipping and party management failures which led to the Syria defeat. The Government’s authority is dented once more by backbenchers who got organised and outdid the official operation.

There are much greater repercussions, though. While good economic news is reassuring some MPs that supporting the Government is an increasingly safe option, and others like Douglas Carswell are moving away from rebellion for reasons of principle and pragmatism, others now see a well-targeted rebel amendment as the best way to get things done – and to make a name for themselves.

Once, ambitious backbenchers could either be slavishly loyal in the hope of promotion, or else they could become a thinker – writing radical pamphlets and erudite books, speaking all around the country, appearing in newspaper comment pages to push new ideas and so on.

Both courses are still open, but circumstances – discontentment, a growing feeling of accountability to voters rather than whips, the hobble of coalition – have opened amendments as a new route. Loads of them sink without a trace, but some (most notably John Baron’s) have sown chaos in Government ranks, forced policy changes and given added clout to their authors.

Each time an amendment hits the target, more MPs start pondering whether they should get it on this game – mismanagement on the scale seen today is only going to accelerate that trend.