Police officers across the United States have shot and killed 847 people so far this year. Mental illness played a role in a quarter of the incidents, according to a Washington Post analysis, and 19 out of 20 victims of police violence were armed in some way.

Some police departments offer de-escalation training to their officers, teaching them to defuse potentially dangerous situations and get armed individuals to lay down their weapons. Most states, however, don’t require such training, instead leaving the decision to local agencies.

The Baltimore Police Department is one agency that teaches de-escalation tactics. A recent example of an officer successfully defusing a potentially violent situation in Baltimore, captured by a police bodycam, shows that these techniques do indeed save lives — and raises the question of why states don’t mandate this training.

Baltimore police Officer Angel Villaronga last month encountered a distraught man with a knife who appeared to be suicidal, encouraging Villaronga to shoot him.

“I’m not dealing with life no more, sir,” the unidentified man said.

“Why?” Villaronga replied. “Officer Villaronga, by the way. You can call me V.”

“Just do your job, man,” the man said to Villaronga.

“This is my job,” the officer replied, continuing to build rapport.

“It’s not your job, a man has got a knife in his hand, he’s … saying he’s gonna hurt someone. … Ya’ll not gonna do nothin’?” the man said, continuing to provoke the officer.

He continued to walk around with the knife, as Villaronga grew closer.

“Why don’t ya’ll want to shoot me?” the man asked, confused.

“Because we don’t want to,” Villaronga responded.

“I don’t want to live,” the suspect continued.

Villaronga instructed his fellow officers, who were across the street, to stay back, then moved in close.

“Just drop it right here, man. I can talk to you,” Villaronga said, empathizing with the man. “I’m 38 years old. I can relate to you, bro. There’s not a thing in this world that I have not dealt with that you probably have dealt with, OK? At the end of the day, I got kids to go home to.”

Those last words did the trick, as the suspect dropped the knife and surrendered to police.

Police bodycam footage released to the Baltimore Sun shows how the incident happened: