Commanders with the Los Angeles Police Department handed out body cameras to officers at one suburban station on 31 August, as the department took a first step in the nation's largest roll out of the technology.

"We are instituting wearing body cameras so body worn video for the officers in this station, every single time a uniformed officer leaves the station to do enforcement or investigative activity from here on out, he or she will be wearing a body camera," said Los Angeles police Captain Jeffrey Bert, a commanding officer present at the pre-dawn distribution of the cameras at the Mission station in the city's sprawling San Fernando Valley.

The move by police in the nation's second-largest city came a day after the mayor of Milwaukee said he would like to spend $880,000 (£573,000) to equip all the city's 1,200 patrol officers with body cameras by the end of 2016. Many US cities have taken an interest in supplying body cameras to officers, following rising tensions and protests over police use of force sparked by several high-profile shooting deaths of unarmed black men in confrontations with officers.

The nearly 9,900-member Los Angeles Police Department (LAPD) is the nation's third-largest city law enforcement force, but is the biggest in the country to commit to equipping all patrol officers, who number about 7,000 officers, with body cameras.

"At this point we are using it as an investigative tool but it is also an accountability tool, it's an accountability tool for the police officer who's wearing it, it's an accountability for the department who is sending the police officer out on the street and it's an accountability for the public as well that we're doing is above board and we're recording it," Bert said.

The American Civil Liberties Union has said body cameras have promise, but that LAPD's plan is flawed because the department has not pledged to automatically release footage to the public, even in high-profile shootings.

Mayor Eric Garcetti has said the technology will build trust. City and police officials on Monday could not immediately say how much it would cost to equip all the department's patrol officers with body cameras. The department plans to distribute the rest of the cameras before the end of 2016 Bert acknowledged that officers may at times make mistakes in using the palm-sized cameras, which they wear at the front of their collar and activate by pressing a button.

"Clearly if someone is tampering with or trying to get around using the camera, the Los Angeles Police Department would consider that serious misconduct, but we also recognize that mistakes are going to happen and sometimes an officer is going to screw up, sometimes you jump out of the car in the heat of the moment because you're focused on something else and the last thing you're thinking about is hitting a button on your chest," Bert said. "We anticipate that is going to happen."

Other jurisdictions around the country are moving forward with the cameras, including Chicago, which has the country's second-largest police force. Detroit said all of its police officers would wear body cameras within three years.

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