The Guardian today has footage of the attack on Ian Tomlinson, who died from a heart attack shortly after being bludgeoned to the floor by a police officer as he tried to walk home from work during the G20 protests.
The news is shocking. I sincerely hope that whichever officer did it is hauled before a court. Depending on what evidence is available, it may be possible to charge him with manslaughter, and perhaps even murder. It's harder, though, to work out what this case tells us about the police. For example, what about the other police officers that went to help Tomlinson when he collapsed? They formed a human shield to protect him from bottle-throwing protesters. With examples of the very good and the appallingly bad within the space of minutes, what do we learn about the Met?
The answer, perhaps, can be found in the Met's own response on the night of Tomlinson's death. Their spokesman appeared to gloss over the avoidable death of an innocent man, preferring to talk about the professionalism of those officers who went to his aid. We need to be cautious - the true extent of the story, including the damaging footage, has only just emerged, and the police may not have had time to formulate a proper response yet. But if they choose to brush this one off, it will tell us something very sinister: that whilst there may be a great deal of bravery and dedication to service on the front line, there is a very cavalier attitude amonst the top brass.
When Jean Charles de Menezes was shot, the upper echelons of the police, together with Ken Livingstone, closed ranks to pretend that it wasn't their fault, and that we should blame the terrorists who created an atmosphere of fear - conveniently forgetting the criminally negligent series of intelligence screw-ups that led to an innocent man being mistaken for a suicide bomber. They compounded that failure by telling lies, and claiming that Menezes had behaved suspiciously: he hadn't. The Menezes case illustrated the gulf of responsibility between front-line officers and policy-makers. You couldn't really blame the men who shot Menezes, because they had been told comprehensively that he was a bomber. Responsibility had to lie with those in the command chain who made grave mistakes, and then lied to protect themselves.
The real test of how the police has moved on from Menezes will be how they handle these shocking events. If we see an open and cooperative attitude towards finding the truth, something vaguely good might have come out of all this. If we see a repeat, where the Met ducks justice, hiding behind the immunity of being a public servant, then we will have got precisely nowhere.