POLICE in Croydon are to wear body cameras to speed up justice and make policing more transparent.
The Metropolitan Police said footage taken by the cameras would lead to more frequent and earlier guilty pleas.
They will be used to record incidents including domestic abuse and public disturbances, as well as police use of controversial stop and search powers.
Commissioner Sir Bernard Hogan-Howe said the cameras would speed up justice and make police more accountable.
"Video captures events in a way that can't be represented on paper and it has been shown that the mere presence of this type of video can often diffuse potentially violent situations without the need for force to be used," he added.
Scotland Yard said officers had been issued with strict guidance about when the cameras should be used.
They will not be permanently switched on and the public will be informed they are being recorded "as soon as practical", a spokesperson said.
The pilot scheme will see 500 cameras distributed among 10 London boroughs: Croydon, Barnet, Bexley, Bromley, Brent, Camden, Ealing, Havering, Hillingdon and Lewisham.
Firearms officers are also testing the cameras with a view to using them at a later date.
Two response teams in Croydon will wear the cameras as they answer 999 calls during the year-long pilot.
The Mayor's Office for Policing and Crime (MOPAC) and the College of Policing will then decide whether the cameras should be made available to the rest of the Met. Camden is the first borough to take delivery of the new cameras.
The chosen camera is the Axon Body Camera manufactured by TSR. It will be attached to the officer's body armour.
It is switched on by either pressing a button on the body of the camera or by sliding a switch across the top. When it is on, a red light is shown.
Officers will "dock" the camera at the end of each shift and upload the material to a cloud-based server. The images will be deleted after 31 days unless they are required for evidence, the Met said.
Sir Bernard said: "Body-worn video will not only help us fight crime and support victims but help the Met to be more accountable.
"Our experience of using cameras already shows that people are more likely to plead guilty when they know we have captured the incident.
"That speeds up justice, puts offenders behind bars more quickly and protects potential victims.
"I believe it will also show our officers at their best, dealing with difficult and dangerous situations every day, but it will also provide clearer evidence when it's been alleged that we got things wrong. That has to be both in our own and the public's interest."
Hampshire Chief Constable Andy Marsh, the National Policing lead for body-worn video, said: "Body-worn video has the potential to transform policing.
"The trial by the Met is the first study of its kind in the UK and has the potential to improve the quantity and quality of evidence that officers are able to capture at the scene of a crime, the transparency of their decision-making and the way officers and the public interact."
The Met has released two videos taken by the cameras and used to successfully prosecute offenders.
One shows officers arresting a man for domestic abuse. On seeing the footage, he entered an early guilty plea and was sentenced to five months. The other shows a man involved in a stabbing who was later jailed for ten years.
The Met believes the cameras could be particularly useful in securing convictions in cases of domestic violence.
Recently released figures show that, while crime fell 9.5 per cent in Croydon last year, reports of domestic abuse increased 15 per cent.
