Lord Stevens warned that failing to explain officers’ actions to the public via the media in a high-profile incident like a fatal police shooting could lead to “massive public disorder”.
He said Scotland Yard officers had become “absolutely terrified” of speaking to the press following the outcry last year over the force’s failure to investigate the full extent of phone-hacking at the News of the World.
The former Metropolitan Police commissioner told the press standards inquiry this was “extremely damaging” for British policing.
He said it was vital for forces to communicate with the public as soon as possible after an incident that could heighten community tensions.
“If you do not deal with that very, very quickly, in terms of saying why you have been involved in a shooting or why you’ve done the actions you’ve done, then the whole thing will escalate in a way that leads to massive public disorder,” he said.
“The message must be out there as quickly as you can, and the media have to be the major part of doing that.”
Lord Stevens, who was head of Scotland Yard from 2000 to 2005, did not refer specifically to the Met’s killing of Mark Duggan in London, last August, which sparked rioting across England.
The police watchdog and Scotland Yard last month apologised for mishandling the way they dealt with Mr Duggan’s family after his death.