Massoud Shadjareh is chairman of a pressure group calling itself the Islamic Human Rights Commission. His intervention in public debate would still have been ridiculous had his hustling been less brazen. Whether there is a civil rights issue of “Islamophobia” is a hotly disputed issue. The notion that the fate of Mr de Menezes, a Roman Catholic, has any bearing on it is risible.

Mr de Menezes was shot because police mistook him for a suicide bomber. The CPS has decided against prosecutions for murder or manslaughter because there is insufficient evidence to provide a realistic prospect of conviction. That would require proving beyond reasonable doubt that the officers did not in fact believe Mr de Menezes was a terrorist. It is surpassingly unlikely that the police would have killed Mr de Menezes at Stockwell Tube station had they not believed there was an imminent threat. Yet the more you examine this line of reasoning that no one is to blame, the more threadbare and less convincing a narrative it appears.

It is easy but wrong to be swayed by the rhetorical absurdity of antiwar campaigners (Bianca Jagger has likened the death of Mr de Menezes to that of Christ). Appeal to commonsense judgment is inadequate. Sympathy with police officers on whose split-second decisions many lives might depend is beside the point. The de Menezes family are entirely justified in feeling that atonement has not been made for a terrible injustice. His death was not premeditated murder, but neither was it an accident. It was a case of mistaken identity about which the answers are as obscure today as they were a year ago.

Leaks of a report, as yet unpublished, by the Independent Police Complaints Commission (IPCC) suggest there will be criticism of the police surveillance operation and of the way the control room operated. The CPS has resolved that the operational errors “indicate that there had been a breach of the duties owed to non employees under the Health and Safety at Work Act 1974”. Failing to provide for the health and safety of Mr de Menezes is a singular way to describe pumping seven rounds of ammunition into his head. The possibility that it will nonetheless prove legally accurate is a sure route to bringing the law into disrepute. Had the CPS ruled that no one bore culpability apart from Mr de Menezes himself, for being in the wrong place at the wrong time, it could scarcely have demonstrated greater official insouciance at the negligence involved.

No fair critic would dispute that the threat of suicide terrorism requires in extremis a readiness to shoot to kill. But there is as yet no convincing account of why the police came to believe that public safety required Mr de Menezes’s death. It is almost literally incredible that armed officers could have trailed him and not realised he was harmless.

The questions that would allay the need for a leap of faith remain unanswered. If the police followed Mr de Menezes from his flat, did they have any grounds for regarding his behaviour as potentially threatening, and if so why did they not apprehend him before he boarded a bus or a train? Did they hear Mr de Menezes speak? If so, were their suspicions in any way allayed, or heightened? Or were the officers unable to tell, so they shot anyway? (I lived in Stockwell for a dozen years, and probably heard Portuguese spoken on every single occasion I walked to or from the Tube. It would be nice to have confidence that the police knew local conditions well enough to be able to distinguish a Hispanic language from, say, a Semitic one.)

There is a point of international comparison. Israel has a policy of finding and killing terrorists who have murdered Israeli nationals. In 1973 Mossad agents killed a Moroccan waiter, Ahmed Bouchiki, in Norway, having mistaken him for one of the terrorists from the Munich Olympics massacre in 1972. It was a catastrophe for Mossad’s counter-terrorist operations, its reputation for being militarily efficient and Israel’s moral standing. Only in 1996 did Israel agree to a financial settlement with the victim’s family; its tardiness and unwillingness to acknowledge responsibility for an act of gross negligence still rankle.

I am, as it happens, a strong supporter of “regime change” in Afghanistan and Iraq, and of Tony Blair’s foreign policies generally. I have little problem with supposedly draconian restrictions on civil liberties that reflect a rebalancing of the system of law against a real terrorist danger. In the case of Israel’s war on Islamist militancy, I believe targeting terrorist leaders for assassination is, in the absence of an effective supranational system of law enforcement, defensible if it deters future terrorist acts.

But these policies need to be allied with a recognition of the extreme fallibility of human judgment, and an ostentatious willingness to acknowledge culpability and make possible restitution for it. From the outset of the de Menezes inquiry — literally from the day of Mr de Menezes’s death — the Metropolitan Police Commissioner, Sir Ian Blair, has given an unmistakable impression of a lack of seriousness. Sir Ian wrote to the Home Office immediately after the killing to say he would not allow access to Stockwell station for IPCC staff. It is not a witch-hunt, but a response to a man lacking a sense of public duty, to demand that restitution to the de Menezes family start with Sir Ian’s dismissal.

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