D.C. Mayor Muriel E. Bowser (D), flanked by Deputy Mayor for Public Safety and Justice Kevin Donahue, left, and interim Police Chief Peter Newsham, answers questions during a news conference Thursday at Anacostia High School. (Joe Heim/The Washington Post)

D.C. police will be required to confirm with dispatchers that they have turned on their body cameras when they respond to a call or interact with citizens, a change ordered this week because an officer who fatally shot a man Sunday did not activate his camera until after he fired.

The mandate comes as authorities continue to investigate the death of 31-year-old Terrence Sterling, of Fort Washington. Sterling was shot early Sunday after police said he crashed his motorcycle into a cruiser. Officers in the car were responding to a report of the motorcycle being driven erratically, police said.

The officer who shot Sterling should have turned on his body camera at the beginning of the pursuit or at the initial interaction, authorities have said.

The new policy, formally announced at a news conference Thursday, is part of D.C. Mayor Muriel E. Bowser’s sweeping effort to address crime in the District.

Last year, D.C. police began equipping all of its patrol officers with the cameras after Bowser (D) proposed purchasing 2,500 cameras at a cost of more than $5 million. So far, about 1,300 of the cameras have been put on the officers. Bowser said she hopes to have the remainder of the cameras deployed by the end of the year.

Ensuring that officers remember to switch on the cameras, especially as they are rushing to answer a call, has been a challenge for police forces nationwide. Having both the officer and the dispatcher verbally confirm that a camera is on provides another level of assurance, Bowser said at the news conference.

“We have given the police officers a new tool. We have to do everything we can to make sure that new tool is being deployed properly,” she said. Bowser added the new policy will serve as a “reminder” for the officers, especially for those who have been on the force for years and who must now become accustomed to flipping the camera switch.

On Thursday, Peter Newsham, the District’s interim police chief, said that over the past 30 days, officers activated the cameras about 55,000 times, recording about 11,000 hours of footage. Newsham said that in that time, there were 10 incidents in which officers failed to turn on the cameras when they should have.

The change is expected to take effect by the end of the week. It will be read at roll calls and included in dispatch newsletters that are emailed to all officers.

The fatal incident began about 4:20 a.m. Sunday when officers got a call about the motorcycle in the Adams Morgan area. Later, police saw the motorcycle near Third and M streets in Northwest. Police have said in a statement that one officer was trying to exit the passenger’s side of the marked car to stop Sterling. But at that point, according to police, Sterling intentionally drove the motorcycle into the passenger door and the officer fired his weapon.

Police have not publicly identified the officer. Both officers in the cruiser — the shooter and the driver — have been put on administrative leave, Newsham said. The chief declined to talk further about the incident because it is under investigation.

“Our number one goal in this particular case is to find out exactly what happened,” Newsham said.

Bowser said footage of the aftermath of the shooting was forwarded to the U.S. attorney’s office as part of the investigation. City officials have asked any witnesses to call 202-727-9099.

Sterling’s father, Isaac Sterling, declined to comment earlier this week and said the family was “dealing with our grief right now” and working to plan Sterling’s funeral.

Jennifer Jenkins contributed to this report.