The pressure finally proved too much for Maria Miller.

Alastair Campbell, Tony Blair's press chief, famously said that if after 10 days a minister was still in the headlines, then he or she was toast - or words to that effect.

The now ex-Culture Secretary did not quite reach 10 days but the constant pressure - press witch hunt according to some colleagues - finally took its toll.

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Of course, on the central charge of using taxpayers' money to pay for a home for her elderly parents, Ms Miller was found not guilty.

But perception is also important.The phonecall from her aide, seeking to warn journalists off the trail with an implied threat over the Leveson proposals, was, to put it mildly, crass.

Ms Miller's own pressure on the standards commissioner and her 30-second apology to the Commons all fed into the impression that some politicians, in the wake of the political earthquake that was the expenses scandal, still don't get it.

Wednesday mornings are often a graveyard for political careers as beleaguered ministers decide not to put the PM through defending them at PMQs, only for them to bail out soon afterwards.

David Cameron will still face a torrid time from a smug Ed Miliband and the baying chorus of Labour MPs this afternoon. Then, there is the little matter of facing his own backbenchers at this evening's 1922 committee.

Will the Nationalists also wade in and seek to decry Westminster for how it handles scrutiny in the wake of the expenses scandal and hope flinging more mud will help the independence cause? The temptation for some might be too great.

In the end, as ever, it comes down to judgement. Mr Cameron has a tendency to stick by his chums - Andrew Mitchell excepted - and perhaps puts personal loyalty too much ahead of political practicality. Andy Coulson may in the weeks ahead prove to be another case in point.

Today's events will send the Conservatives and their leader off into the Easter recess bruised and even more fearful about what might happen in next month's Euro elections. But they prove yet again, politics can be a brutal old game.