The Sketch: Smiling through it all, Gordon wanders into a bog

We're not used to this, a polite, attentive, well-behaved House of Commons. Row upon row of them sitting there – shy, ashamed and silent like chastised schoolchildren from an earlier era. Four hundred-odd people found guilty in the Court of Public Opinion (© Harriet Harman) and sentenced to be quiet. Oh, cruel punishment.

The PM has washed his hair. That's news. Every day he makes a greater effort to be decisive, forceful, in command. At PMQs we heard this: "Leadership is me saying to all the political parties that they have got to act immediately." Is that really what leadership is? Say it out loud to yourself, in the privacy of your own bathroom (you wouldn't want anyone to hear). "Leadership is me saying..."

Every day we see more of the way he works and what he is. Every day we understand more. It works against him, I fear. In Gordon's case it's: " Tout comprendre, c'est tout condamner."

He told us again how important it is that people outside Parliament make the rules for parliamentarians, only that way will trust in politics be rebuilt. In other words: "The public think we are so corrupt, venal, greedy and lazy that we can't be relied on to wash our own linen. And what's more – I agree with them!" It's a terrible judgement, but when you look back over the way they have treated whistleblowers, corrupt MPs, ombudsmen and watchdogs, he's probably right.

Cameron (who has half a dozen instantly applicable ideas to keep ahead of the game) asks sharply: "How can we bring about the change this country needs if we cannot change ourselves?"

But another question lies underneath that: "If we are so morally defective, so ethically inferior... how do we stand up in front of the nation's doctors, nurses, teachers and sketch writers and tell them how to conduct themselves?"

Gordon has made a second fateful proposal. His plan is to go back four years and uncover every receipt from every MP and examine every payment made.

It is an error that only someone driven by politics could make. He has found himself needing to go one step further than the Tories so has blundered into a bog. What MPs claimed before they feared exposure will out-smell anything we've experienced so far. And the reputation of MPs will sink ever deeper into the mire.

There's no sense in his proposal, no justice, no fairness, no profit. It will expose MPs to a year of ridicule, contempt and trivia.

So it's not all bad. We'll go along with it. He is the Prime Minister after all. PS: One positive point. The smiling has improved. "I am pleased to announce," he said and smiled through the words "am pleased to".