Azelle Rodney was shot six times in 2005
A Met Police marksman has lost his High Court bid to challenge a public inquiry finding he used excessive force when he killed a robbery suspect.
Last year, an inquiry decided there was "no lawful justification" for the marksman to have shot Azelle Rodney six times in Edgware, north London in 2005.
But lawyers for the officer, known as E7, said the finding was "irrational".
E7 was seeking permission for a judicial review over the inquiry's conclusions.
The inquiry chairman Sir Christopher Holland concluded Mr Rodney was unlawfully killed, a finding E7's lawyers described as "tantamount to murder".
Police believed Mr Rodney was on his way to rob Colombian drug dealers
But Sir Brian Leveson, president of the Queen's Bench Division, sitting with Mr Justice Irwin ruled there was "no value in granting permission" and refused the application.
Mr Rodney was shot after the car he was travelling with two other people was stopped by armed police.
Detectives say they had intelligence the 24-year-old was on his way to rob Colombian drug dealers.
E7 opened fire within a second of coming to a halt beside the car, hitting Mr Rodney once each in the arm and back and four times in the head.
E7's justification for firing was that he "honestly believed" Mr Rodney was preparing to fire a machine gun. Sir Christopher, a High Court judge, rejected that claim.
Samantha Leek QC, representing E7, told the High Court earlier this month: "We say it is not a logical conclusion, either on the forensic or eyewitness evidence, that E7 did not honestly believe there was an imminent threat to his colleagues' lives."
But dismissing the point as "unarguable", Sir Brian said: "The hurdle of proving that Sir Christopher reached irrational conclusions on the facts is incapable of being surmounted."
The Met had backed his application for a judicial review which has been opposed by a legal team acting for Sir Christopher who have argued that E7's legal challenge was "untenable".
E7 could face criminal trial over Mr Rodney's death and prosecutors are considering whether to bring charges.