This burglar doesn’t realize he’s got about a minute to get his work done before the Scottish police turn up. It’s interesting seeing British commenters complain that he was treated too roughly by them, while the American ones marvel that he wasn’t executed on the spot.
My guess is the copper didn’t see the crowbar until right on top of him in the cramped backyard, creating an opportunity for the burglar to strike and thereby necessitating a pre-emptive beating that sadly lacks the usual jaunty interaction between British police and suspect, the extended ironic ruminations on the nature of crime and the inevitability of justice, the perverse yet socially reinforcing affectations of honor and fair play, the tea and biscuits down the station, etc., that are the usual hallmarks of modern British policing and its interactions with the criminal element.