Theresa May had no alternative but to sack Damian Green

The crises keep coming and yet she carries on; the leader with the kitten heel shoes seems to have nine lives

Green's departure rounds off a rollercoaster year for May (PA)

Damian Green had to resign because he forgot rule one of political scandals: it’s usually the cover-up rather than the original offence that gets you.

The former Channel 4 journalist should have known better. He should have thought like a journalist rather than a politician and remembered one of the greatest scoops of all time – the Watergate scandal which led to the resignation of the US President Richard Nixon in 1974.

The killer facts for Green were two outright (if contradictory) denials he issued last month about allegations that pornographic material was found on a computer in his Commons office in 2008. The investigation by Sue Gray, the civil servant responsible for ethics at the Cabinet Office – the department Green headed – found that his statements were “inaccurate and misleading”. It discovered that the Metropolitan Police told Green’s lawyers about the discovery in 2008 and that Green himself was told in a telephone call in 2013.

Crucially, last month’s denials were made while Green was a minister, which meant he was covered by the ministerial code requiring ministers to be honest. He was not covered by it in 2008 as he was an opposition spokesman then. The inquiry reached “no conclusions” on whether Green viewed the porn, which he strongly denies.

If the former Deputy Prime Minister had said nothing last month, it is possible that he could have survived in his post.

The allegations of inappropriate behaviour towards journalist Kate Maltby in 2015 (when he was not a minister) were “plausible”, the Cabinet Office found. But it was “not possible to reach a definitive conclusion on the appropriateness of Mr Green’s behaviour". On its own, that would have left Green in a grey area; Theresa May might have been able to hang on to her closest political ally. In the end, the inquiry's findings were more clear cut than many at Westminster had expected. The code had been breached, and so May asked Green to resign.

There really was no alternative for the Prime Minister. She took a hard line against Sir Michael Fallon, another loyalist, telling him to resign as Defence Secretary last month when the sexual harassment allegations spread from Hollywood to Westminster. She would have been accused of double standards if she had tried to allow Green carry on; if anything, the case against him was clearer than against Fallon because of his recent misleading statements rather than behaviour several years ago.

May might get some credit for being tough on sleaze. Even though Green was not found guilty of inappropriate behaviour towards Maltby, his resignation will send a signal to women that May takes such allegations seriously.

Some Tory MPs will feel sorry for Green and regard him as a victim of a witchhunt by current or former police officers - like the former International Development Secretary Andrew Mitchell, who quit after allegedly calling police at the gates of Downing Street “plebs”, which he denied. But in one sense Green has only himself to blame for issuing statements last month that he now admits were not accurate.

His departure rounds off a rollercoaster year for May. She is lucky that the findings of the Green inquiry did not emerge at a more difficult time for her; there have been many of those. Indeed, there is bound to be a suspicion that the findings have been delayed. As things stand, May has a breathing space after winning a phase one Brexit deal last week.

There have already been several occasions when Tory MPs declared that May is one mistake or crisis away from the exit door. The crises keep coming and yet she carries on; the leader with the kitten heel shoes seems to have nine lives.

As they departed Westminster for the Christmas recess before Green’s resignation, the joke among Tory MPs was that May offers “weak and stable” government. Many a true word….