Changes to the law are needed to restore public confidence after people are shot dead by firearms officers, the police watchdog has said.
The Independent Police Complaints Commission said it was “extremely frustrated” by obstacles preventing officers being more transparent with relatives.
Deborah Glass, of the watchdog, spoke out after it emerged an inquest into the death of the man whose shooting triggered last summer’s riots could be impossible because of “disclosure issues”.
The IPCC may have material “that it could not properly disclose to a coroner” over the decision by officers to shoot Mark Duggan, North London coroners’ court was told this week.
Ms Glass, the watchdog’s deputy chairwoman, is calling for a change in some sections of the Regulation of Investigatory Powers Act, which bars some evidence from legal proceedings. The IPCC believes that it is “essential for families to play a full part in any process which establishes how and in what circumstances their family member died”.
Both the IPCC and Scotland Yard have admitted mishandling the way they dealt with Mr Duggan’s family. Mr Duggan was a passenger in a minicab when he was killed during a planned operation involving officers from the Met’s Trident unit on August 4 in Tottenham.
The IPCC is still conducting a separate investigation into the shooting, with an investigation into his death failing to establish the sequence of events concerning a handgun found at the scene.
