With ever-growing public scrutiny regarding police-involved shootings, a Maple Plain company that manufactures weapons accessories is testing a miniature camera that attaches to the barrel of an officer’s gun.

The 3.2-ounce, 3-inch-long camera sits in front of the trigger and activates video and audio as soon as an officer pulls the gun from the holster. The camera points in the direction the muzzle is pointed.

Several police departments have offered to try out the cameras as a pilot project, including the West Hennepin Public Safety Department that covers Independence and Maple Plain and a police department in Arizona.

“As we’ve seen, there have been a lot of high-profile incidents over the last few years where it’s not really clear what happened, and this is meant to provide that missing piece of evidence,” said Brian Hedeen, president of Viridian Weapon Technologies, the company that’s making the camera that it has dubbed the Fact Duty.

The camera attachment also includes a small light, about the strength of a flashlight, that faces forward.

Production is about to begin on the cameras, and Hedeen said he hopes to have them in the hands of police departments to try out in October.

“[Viridian] asked if we would review the product,” said West Hennepin Public Safety Director Gary Kroells. “We like the concept.”

Kroells cited the July 15 fatal shooting of Justine Rusz­czyk Damond by Minneapolis police officer Mohamed Noor after she called 911 to report a possible sexual assault behind her home. Neither of the responding officers’ body cameras were on at the time of the shooting.

“Possibly, a weapon-mounted camera would have captured it,” Kroells said.

His department has 10 officers, and he plans to outfit three or four of them with gun cameras. He estimated that officers in his department usually draw their guns about once a month but not normally in deadly force situations.

Herman Nixon, chief of the 14-member police department in Williams, Ariz., said he got interested in the cameras after one of his lieutenants saw them at a firearms expo in Las Vegas.

Nixon said his department has not had an officer-involved shooting since 2003, but his officers usually have to draw their guns two or three times a month. He said that if he likes how the cameras work in the pilot project, he plans to buy them for all of his officers.

The cameras, purchased in bulk, cost about $500 apiece, according to Hedeen.

While the camera turns on automatically when the gun is drawn, police departments and/or officers must decide whether the light also will automatically activate. In some instances, officers might not want a light to come on and reveal their location, so the video might reveal little in some nighttime situations.

The cameras may have an advantage over body cameras in some scenarios. If an officer is firing a gun from behind something solid such as a patrol car, the car could block the bodycam lens, whereas the camera attached to the gun would most likely have an unobstructed view.

Teresa Nelson, interim executive director of the American Civil Liberties Union of Minnesota, said she is intrigued by the idea of gun-mounted cameras, especially because they are activated automatically and don’t require an officer to turn them on, as with body cameras.

“We’re in a moment right now when the community is demanding more transparency and accountability from police officers in the way they do their jobs and use force; tools that can provide that transparency, I view as a good thing,” Nelson said. “They are never going to be an end-all and be-all, but it is another source of information.”