Lawyers for the family of Brazilian man Jean Charles de Menezes are today expected to be updated on the investigation into his fatal shooting by armed police in London.
Mr Menezes (27) was shot after being mistakenly identified as a terrorist on the Tube, and his relatives have called for a public inquiry into his death.
Their supporters say that Scotland Yard chief Sir Ian Blair must resign if he is found to have deliberately misled them over the killing at Stockwell Tube station.
Their lawyers also say a "fatal delay" by police in triggering an independent investigation could have led to the loss of vital evidence.
Former cabinet minister Frank Dobson said Sir Ian's position was "very difficult" as he was partly responsible for people being misled.
Police "have allowed the false impression, the misleading impression that this man was behaving suspiciously" which was "very disturbing", he added.
Independent Police Complaints Commission documents obtained by ITV Newshave shown a catalogue of errors leading up to the shooting.
Further revelations from the leaked papers last night suggested that Mr de Menezes was identified as a target to armed police just seconds before he was killed.
An undercover surveillance officer shouted "he's here" and pointed at the innocent man before colleagues pumped seven bullets into his head.
Mr de Menezes, an electrician, was at first thought to have aroused suspicion by wearing a heavy padded coat, vaulting ticket barriers, and fleeing from police.