Ken Livingstone has said the police officer in charge when Jean Charles de Menezes was shot has the "potential" to be a future Met Police Commissioner.
A jury returned an open verdict at the inquest into the electrician's death.
The former Mayor of London said Cressida Dick was one of the "most talented" officers he had worked with. But Gareth Pierce, a lawyer for the de Menezes family, said 25 "serious and catastrophic" failures by Ms Dick alone had been identified.
Brazilian Mr de Menezes, 27, was shot dead on 22 July 2005 at Stockwell Tube station when he was mistaken for a suicide bomber.
In an interview with BBC Radio 4's Today programme, Mr Livingstone said the police officers made mistakes because of the "unbelievable" pressure they were under.
Ms Dick, who was in command of the operation and subsequently promoted, had "commissioner potential" he said.
Source: BBC News
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