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."
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