PM also is now under pressure to sack his chief-of-staff, Ed Llewellyn, for his alleged failure to bring important warnings to his attention.

Yesterday's revelation by Rebekah Brooks that it was George Osborne, in fact, who gave the advice to appoint Mr Coulson, only adds to the Tories' embarrassment. If Mr Cameron is lucky, the recess will mean there are fewer opportunities for damaging public debate of the issue, but it shows few signs yet of burning itself out.

But yesterday's hearing of the Commons media select committee hardly gives MPs grounds for self-congratulation. With the exception of Labour's Tom Watson, they hardly landed a punch on the Murdochs. There remain many important unanswered questions about who in News International knew what and when. The admission that it paid legal fees for the two men convicted for hacking in 2007 raises important questions about its responsibility for their actions.

Meanwhile the report of the home affairs committee is unsparing in its judgment on the Metropolitan Police: the MPs accuse the force of a "catalogue of failures" to investigate the phone hacking allegations. The resignation of the most senior officers in the force has not taken pressure off the Met to explain its close involvement with News International.

Today's debate shows no sign of relieving pressure on the Prime Minister. Rather, it reminds us of the distance that this profoundly damaging scandal still has to run.