CHICAGO -- Chicago authorities say all police officers will be equipped with body cameras by the end of 2017, a year ahead of schedule.

Mayor Rahm Emanuel says in a Wednesday statement announcing the speeded up schedule that body cameras “improve transparency while building trust.”

Scrutiny of police intensified after the release of a squad-car video last year ago showing a white officer fatally shooting black teenager Laquan McDonald 16 times. The Justice Department launched a civil rights investigation and Emanuel pledged sweeping reforms. The city launched its body-camera program in 2015 and expanded it following protest over the McDonald video.

Wednesday’s statement didn’t include costs or camera numbers. But police said in September that 2,000 body cameras were in use and that 5,000 more would be bought for around $8 million.

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By the end of next year, it is a task every Chicago patrol officer will be expected to take before hitting the street, because by then, each one will have a body camera, CBS Chicago reports.

“Turn the camera on at the beginning of your tour of duty,” said Chicago Police Commander Marc Buslik. “The switch is flipped over.”

“The net benefit is greater safety and security to our officers and an overall improved interaction with our communities,” Cmdr. Buslik said.

The city’s body cam pilot program launched in the Shakespeare district in 2015. Then expanded to six more districts last year.

The budget passed by city council included $2.8 million to expand to seven more districts, but another $2.8 million, from money that was not needed for the property tax rebate program, is now being used to complete a citywide roll-out one year ahead of schedule.

“The policy is the officer will turn on the camera,” Cmdr. Buslik said. “They are being held accountable for doing so.”

But the officer who shot and killed Paul O’Neal last August, after a wild car chase and then foot chase, did not have his camera on.

“The officer had just recently received the camera as they had in that district,” Cmdr. Buslik said.

Like any other piece of technology, it is a question of getting used to it.

Fraternal order of Police President Dean Angelo said that officer was new to the camera, and though he’d turned it on, but turned it off by mistake.

“We want to make sure they are trained properly beforehand,” Angelo said. “We don’t want officers vilified for an honest mistake.”

Dean Angelo told CBS 2 he is also protesting because the FOP was not notified about the body cam expansion before the announcement, as they should have been.

The city may also be aiming to get ahead of the ongoing federal investigation into Chicago’s police. The Justice Department has recommended body cams as the result of similar investigations in other cities.