It's about trust — that was the message from Mayor Bill de Blasio and Police Commissioner James O'Neill as they announced plans Tuesday to equip all police officers and detectives on patrol with body cameras by the end of the year. That's more than 18,000 of them. 

"It's a de-escalator, complaints are quickly resolved, officer safety is an issue here, we can use it for training purposes, and one thing I like the most out of this is that people get to see the reality of police work," O'Neill said.

The plan is being rolled out a year earlier than previously announced. More than 2,400 officers currently wear the cameras, some of them as a result of a court-ordered pilot program involving stop-and-frisk. The NYPD said it will roll out between one thousand and two thousand cameras per month, beginning in March.

"This is still a relatively new thing, but officers have taken to it very quickly, and what we're seeing now is far superior to the information we used to have in the past, so I think we're on a good trajectory," de Blasio said.

The mayor has set aside money — more than $27 million over three years — in the city's preliminary budget to pay for the accelerated rollout to support the program.

But the Patrolmen's Benevolent Association opposes the cameras, arguing they violate officers' rights. The union also questions whether they "produce a meaningful change in the interaction between police officers and civilians on the street."

NYPD brass and the mayor disagree: "They ensure the community members feel the power of transparency. They build trust through transparency," the mayor said. "Also better for our officers; you get a clear and definitive record of what happened in any encounter."

The announcement comes on the heels of several recent police-involved shooting in the city that were caught on body cameras, including one Monday night in the Bronx. The NYPD said that footage will be released but there is no timetable for that to happen — one of the ongoing complaints about the program.