Sketch: Cameron wanted good news, but got unearthly silence

Whatever else is happening, it was clear yesterday that nothing grips a noisy House of Commons more completely than the whiff of really toxic scandal, past or present. Especially in the post-Savile climate.

A lot happened at Prime Minister's Questions yesterday. First David Cameron ended a boisterous series of exchanges with Ed Miliband on energy policy and the West Coast main line by taunting Labour with a bold claim in the wake of better figures on unemployment and inflation that "Every bit of good news sends [Labour's] team into a complete decline, but I can tell the right honourable gentleman that the good news will keep coming."

This sparked an immediate and furious row over whether Cameron was leaking the growth figures that will be published today. More pertinent for the rest of us, however, may be whether the good news really will "keep coming" after that? Or will he be forced, as his old boss Norman Lamont once was, to tough out criticism for prematurely detecting "the green shoots" of recovery?

Earlier Cameron had appeared to defy a ruling by the European Court – and his own Attorney General – by promising to deny prisoners the vote. The Attorney General had suggested a European ruling against Britain's blanket ban on prisoners' voting could have a degree of "flexibility". But what could this mean? That Barlinnie inmates, for example, will be allowed to vote in the Scottish independence referendum but not in the general election? One idea is that judges would include the voting ban in sentences. But they would surely insist on discretion, with barristers pleading: "My Lord, my client is passionate about the political process. It will severely set back his rehabilitation if he cannot vote in the coming election."

But none of this compared with Tom Watson's command of a hushed House, including a clearly shocked Prime Minister. You could almost hear MPs watches' ticking as the Labour MP said he wanted to ensure that the Met re-examine the evidence in the Peter Righton paedophile case and "investigate clear intelligence suggesting a powerful paedophile network linked to Parliament and No. 10."

Cameron, who had lent forward intently as Watson was speaking, said that "I am not entirely sure which former Prime Minister he is referring to. What I would like to do is ... look carefully at what the Government can do to help give him the assurances he seeks."

Partly, of course, the MPs are aware that the scourge of Rupert Murdoch usually knows what he is talking about. The satisfaction of making MPs laugh on both sides of the House is well known. But an intervention that shuts them up is even rarer.