Body-worn cameras will help "to get better convictions" because the filmed evidence against them will be robust, the head of the Metropolitan Police told Good Morning Britain.
Bernard Hogan-Howe said some evidence was "really hard to capture" with a written statement and providing film would help the victims of crime.
"Secondly, it helps to get better convictions because it is such compelling evidence and quicker because often people will plead guilty when they know that sort of evidence is against them."
More top news
Madonna says she still cannot bring herself to watch footage of the moment she fell on stage while performing at the Brit Awards.
Ed Miliband has pledged to give zero-hours workers the right to convert their contract into a regular job after three months.
More than 100 leaders have declared their support for a Conservative-led government, warning a Labour would "put the recovery at risk".