One of Britain’s most senior anti-terrorist policemen told the inquest into the shooting of Jean Charles de Menezes yesterday about the personal strains experienced by officers during July 2005.

Deputy Assistant Commissioner John McDowall said that during the month of the 7/7 and 21/7 bomb attacks in London he was able to spend the night at home only once.

On the night of July 21/22, when he and his team were beginning a manhunt for four would-be suicide bombers, Mr MacDowall, 51, said he slept for only two hours.

Mr de Menezes was shot dead at Stockwell Underground station when he was mistaken for one of those fugitive bombers.

Because of a serious illness which means that he has to use a wheelchair, Mr MacDowall gave his testimony via videolink. David Perry, QC, representing Mr McDowall and other senior Metropolitan Police officers, asked him: “Are you still happily married?”

The officer, head of Scotland Yard’s Counter-terrorism Command, replied: “Just about, sir, although, sadly, I don’t have my health — I don’t know whether that has got anything to do with it.”

Mr McDowall devised the police strategy for surveillance of a block of flats in Tulse Hill, South London, associated with one of the 21/7 bombers, Hussain Osman.

Officers followed Mr de Menezes, 27, a Brazilian electrician, from the flats suspecting, but never confirming, that he was Osman.

Police firearms officers were deployed to “stop” Mr de Menezes but were late arriving at the scene and shot him seven times in the head on a Tube train.

Mr McDowall told the inquest, sitting at The Oval cricket ground, that firearms officers should open fire only if they have definitely identified a suspect.

Sir Michael Wright, the coroner, asked him: “You are not suggesting that at any time you would contemplate an armed officer taking a critical shot on the basis of a less than positive identification?”

Mr McDowall replied: “No, that’s correct sir.”

The officer said that it would be for officers involved in an armed operation to judge whether the information they had justified using guns.Mr Perry asked: “If you think someone is going into a transport system and that they are going to cause hundreds of casualties, you may have to make a judgment balancing the risks?”

Mr McDowall said: “Yes, it’s a judgment about whether what you have is sufficient to mount that operation or not.”

The inquest continues.

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