He probably won it in the chamber but probably lost it in the briefing huddle afterwards. He was almost playful at the dispatch box – and enjoyed the biggest show of force from the Eurosceptic right we've seen in the Commons. That's quite a body of opinion when you see it on the benches. It is the constituency Mr Fox will be presented to, if he's kicked out of Cabinet.

His defence? With the benefit of hindsight ... In probity he ... Beyond this, nothing. As transparent as possible. Remove the appearance of wrong doing. I made clear that ... Accept my personal responsibility.

An apology always brings out the sentimental side of the Commons. It awakes an ancestral memory of something that used to be called shame and is now known as embarrassment. When he sat down, his survival was still in the balance.

Jim Murphy began by reminding the house of his interests and he named and numbered the many clauses of the ministerial code which Fox had admitted to breaching. The material was good, but Jim Murphy's delivery is as dull as the drone of a bass bagpipe, if such a thing exists. He lacks the accusative power of, say, John Reid.

Fox's reply contained a single destructive punch: why hadn't Mr Murphy declared what that interest was? Labour's Defence front bench had accepted £10,000 from Fox's enemies in this affair. Suddenly you couldn't easily see what was going on. Flying mud filled the chamber.

In the huddle outside, the Fox victory evaporated. The hacks got on to, among other things, the money. Not that Fox had made anything himself. But if nothing improper happened, how did Werritty make his living as a defence lobbyist? And crucially, was Werritty's client list going to be investigated?

The officials' voices rang not true and clear on this. One of the hacks summed it up with the observation: "You're saying that Fox and Werritty met 40 times in 18 months and they never discussed business? He's not a very good lobbyist, is he?" And the balance dips again.

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