MANCHESTER — Police will begin a 30-day tryout of body cameras for police officers later this month, with the expectation that all police officers will eventually wear body cams, top officials said Wednesday.

Police Chief Carlo Capano said 12 officers will pilot the cameras starting Feb. 19. The evaluation period could be extended, he said.

Capano spoke as a trial moved into its second day in Hillsborough County Superior Court. Most of the trial hinges on a civilian-filmed video that does not capture a key point during a melee, when prosecutors say the alleged attempted murder took place.

Capano said the Georgia-based company BodyWorn will supply the equipment, upgrades and computer storage for the system.

He estimated it will cost $1 million to $1.5 million over five years.

In 2017, a state law went into effect addressing body cameras. The law does not require or prohibit their use by local departments, but it lays down provisions about training, when videotaping can take place, what happens to the data, how long it can be stored and how much is subject to the Right-to-Know Law.

Big departments such as Manchester, Nashua and state police have not adopted body cameras, according to recent news accounts.

Capano made the announcement at the monthly meeting of the Manchester Police Commission. Mayor Joyce Craig, who attended the meeting, later said that aldermen are overwhelmingly in favor of body cams for police, and it’s a matter of safety for police.

“It’s important. We need to include it (in the upcoming budget),” Craig said.

“This particular product adds numerous levels of officer safety,” Capano said. He did not elaborate, but on its website BodyWorn stresses that the camera turns itself on based on certain triggers, which allows officers to concentrate on the task at hand.

Those include:

Gunshot detection. When a gunshot is detected, the camera begins recording and recalls two minutes of audio and video prior to the shot. The camera sends a call-for-help message, which reports the officer’s location.

Officer down. If an officer becomes prone and needs backup, BodyWorn starts recording and sends an alert to all nearby officers, along with GPS coordinates.

Vehicle sensors. The camera decides when to start and stop recording during during certain vehicle-triggered events such as lights and sirens and a door opening.

Motion. A built-in accelero-meter can detect when an officer starts running and triggers a recording.

Action zones. The camera can automatically turn on or off based on pre-defined action zones.

Capt. Brian O’Keefe said plans are to have every sworn police officer eventually equipped with a camera.