Leading article: A question worth asking

There have long been two questions hanging over the tragic killing of Jean Charles de Menezes, the Brazilian electrician shot dead by police on the day after the attempted London bombings. The first was the obvious one: how could it have come about that an innocent man was mistaken for a terrorist and shot at point-blank range on the London Underground. The Independent Police Complaints Commission announced a formal investigation into the shooting soon afterwards, as it is required to do.

Very soon, however, a second question reared its head: why was so much of the information initially released by Scotland Yard so misleading, and why was the Metropolitan Police seemingly so slow to correct the record? A leak of interview transcripts from the IPCC investigation in August suggested that this was a question worth asking. It will now, as announced yesterday, be the subject of a separate IPCC investigation that will consider the conduct of the Met's commissioner, Sir Ian Blair.

This is a welcome development. The circumstances of De Menezes's shooting are one thing, which relates as much to operational procedures as to judgements. How the Met subsequently presented what happened is something else - and it is right that the two should be kept distinct. It is also right that Sir Ian's handling of the killing should be scrutinised. We have seen too many inquiries where the matter of personal responsibility has been skirted, because the terms of the investigation have been framed to exclude it.

The Metropolitan Police have rarely needed the goodwill of the public more than they have since the London bombings. The De Menezes killing and its aftermath seriously undermined it.

But the timings and the veracity of what he said need to be tested. Just when was Sir Ian aware that an innocent man had been killed? Why were the false details of the pursuit allowed to linger? And precisely what were the circumstances in which Sir Ian asked the Home Office to block the IPCC investigation into the shooting? Rebuilding the public's faith in the police will be an uphill struggle for the Met, and for Sir Ian, until these questions have been fully answered.