The shooting of Jean Charles de Menezes has ignited debate about a 'shoot-to-kill' policy and the position of Metropolitan Police Commissioner Sir Ian Blair.
Political Editor Jonathan Walker considers the background while Barney Smith, from the Green Party, and Alun Thorne give their views...
The day after terrorists attempted to set off four bombs in central London, a young man was shot seven times in the head by armed police.
It soon emerged that Jean Charles de Menezes, a 27-year-old electrician from Brazil, was the victim of a tragic mistake.
Initially, there was widespread sympathy for the police, who had apparently believed Mr de Menezes was a suicide bomber.
But now the mood has changed, following a series of revelations which raised serious questions about both the shooting, and the behaviour of officers afterwards.
The spotlight has fallen on Sir Ian Blair, the Metropolitan Police Commissioner.
For London Mayor Ken Livingstone, he is the ?best news? the force has got.
But Birmingham MP and former Cabinet Minister Clare Short has demanded a public inquiry, claiming: ?We?ve been lied to?.
The family of Mr de Menezes, meanwhile, have called on Sir Ian to resign.
Soon after Mr de Menezes was killed at Stockwell Tube station, on July 22, reports emerged that he had been approached by police but ignored their demands to stop.
Instead, he jumped over a ticket barrier and ran on to the train. Furthermore, he had been wearing a winter coat, despite the warm weather, leading to suspicions he was concealing some sort of explosive device.
In other words, he behaved exactly like a potential suicide bomber and, it was implied, his attempt to run from the authorities had contributed to his death.
Some of these reports came from eye-witnesses, who may have been mistaken.
But Sir Ian himself justified the killing by explaining: ?This shooting is directly linked to the ongoing and expanding anti-terrorist operation . . . as I understand the situation, the man was challenged and refused to obey police instructions.?
And a Metropolitan Police spokesman told journalists: ?His clothing and his behaviour at the station added to their suspicions.?
The family of Mr de Menezes denied all these suggestions. And earlier this month, we learned they were right.
Leaked documents from an Independent Police Complaints Commission investigation into the shooting confirmed that he walked through the barrier with an ?Oyster card? ticket in the normal way, wearing a denim jacket.
He sat calmly on the train ? with three surveillance officers watching ? until armed police stormed in and shot him.
It also emerged that Sir Ian had asked the Home Office to block the investigation, insisting that the Metropolitan Police should have an internal inquiry instead. And there is continued uncertainty surrounding police claims that no CCTV footage from the platform or train exists.
Sir Ian was quick to criticise West Midlands police officers when they used a Taser gun, which fires electric charge of 50,000 volts into the victim without killing him, on a suspected suicide bomber in Birmingham.
He described it as ?an incredible risk?, because the charge could have set a bomb off.
It is almost unheard of for one senior police officer to criticise another force in this way and critics claim Sir Ian was covering his own back, by justifying the use of bullets rather than Tasers.
What is certain is that the spotlight is on the Metropolitan Police and its shoot-to-kill policy.
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