Going by the media outrage over shadow immigration minister Damien Green’s arrest, the entire Tory front bench should seek to get its collar felt. The right is discovering what the left long ago learned. There’s nothing so chic as a policeman’s truncheon.

Doubtless in fact this was just a bit of good luck the Tories stumbled into. But it repositions them as a real opposition rather than as an out-of-touch Toff Tendency. How dissidence becomes a politician.

Labour is on the defensive. It is accused of and forced to deny Stalinist tactics. Perhaps they knew about the arrest in advance, perhaps not. Perhaps they sort of did and rightly did nothing. PC plod perhaps did it off his own bat for good reasons (the media and the Tories could yet be forced to eat humble pie if real crimes are proved to have been committed or were decently suspected).

This story wobbles in many directions in our imaginations precisely because we don’t know the full facts yet.

But as any author knows, nothing attracts readers (voters) like a good old ban or witch hunt against an undeserving target. Matthew d’Ancona said in yesterday’s Sunday Telegraph the arrest has transformed the Tory image from Bullingdon boys to Woodward and Bernstein (though nobody accuses the government of committing a crime, unlike President Nixon).

My gut instinct tells me that this will not end in a clean win for anybody – not the police, the Tories, the civil servant involved, or the Speaker of the House. There’s a good chance that as the truth gets told and the events chronicled as to who did what and knew what when and why, the waters will muddy.

Still, the Tories may well hang on to their PR victory. There is a huge appetite for government openness and establishment-clobbering. The fine tuning won’t matter. Damien Green is very likely to keep his trusty sword of truth and his breastplate of indignation, or whatever it was that Jonathan Aitken couldn’t quite keep hold of.