WEB-EXCLUSIVE, LONGER VERSION: Poor, brave David Davis has become the Eddie the Eagle of Westminster 

At a dinner party in central London a few months ago, David Davis made an extraordinary confession. He had become disenchanted with David Cameron, he said, and was considering quitting politics. ‘I believe in certain things,’ he claimed, ‘and I do not believe the next Conservative government will implement them.’ He wondered if he should try to earn a little money in the outside world. He did not come across as bitter or regicidal, I am told, just disillusioned — and planning a graceful exit.

Or, as it turned out, a rather spectacular one. It is now more than a week since Mr Davis resigned to campaign on the issue of civil liberties, and MPs are still comparing theories. No one denies he is genuinely committed to the cause, but no one can understand why he believes he could achieve more from the backbenches than as Home Secretary. Some argue that he’s angling for a peerage, or hopes to come back to Westminster with a populist halo. But given that he’s certain to be re-elected next month, the question on everyone’s lips is how Mr Cameron handles him then.

So many theories abound about Mr Davis’s ‘real’ intentions that the most damaging possible explanation — a loss of faith in Mr Cameron — has hardly been mentioned.
Their differences over issues such as tax, grammar schools and defence spending are hardly a secret, having been extensively aired during the leadership contest. They were also said to disagree over Mr Cameron’s plans for locally elected police chiefs — Mr Davis asking what a home secretary would have left to do if policing was devolved. Mr Davis ferociously denies any such splits, but anecdotal evidence to the contrary has been accumulating for some time.

One of his friends says that, ‘It wasn’t 42 days that did for David, but 42 Old Etonians.’