But the fatal shooting of 19-year-old Tony Robinson has its own unique set of circumstances.
The deadly confrontation has made Madison, Wisconsin, the latest epicenter of protests. Demonstrators plan to rally there at the Wisconsin State Capitol on Monday morning, and students say they will stage a walkout at the city’s East High School after classes.
Here’s what we know about the Friday night shooting.
The incident started when authorities got a call that a black male was yelling and jumping in front of cars, Madison Police Chief Mike Koval said.
Dispatchers identified him as Tony Robinson, according to 911 audio obtained by WKOW.
A little later, the dispatcher says, “Apparently Tony hit one of his friends. No weapons seen.”
About four minutes later, the dispatcher says, “I got another call for the same suspect at [the same address]. He tried to strangle another patron.”
About 30 seconds later, an unidentified officer says, “Shots fired, shots fired.”
When Officer Matt Kenny went to the apartment, he heard some commotion and forced his way in, Koval said.
“Once inside the home the subject involved in this incident — the same one allegedly out in traffic and that had battered someone — assaulted my officer,” Koval said.
After that, according to the chief, “The officer did draw his revolver and subsequently shot the subject.”
Even Koval said it’s understandable why protesters are outraged.
“He was unarmed. That’s going to make this all the more complicated for the investigators, the public, to accept, to understand … why deadly force had to be used,” he said.
This isn’t the first time Kenny used lethal force.
In 2007, he shot and killed a man in what the police chief described as a “suicide by cop.”
Kenny was exonerated of any wrongdoing and even received a commendation.
During the confrontation Friday night, Kenny suffered a blow to the head, Koval said. He has been placed on paid administrative leave pending an investigation.
Under Wisconsin law, officer-involved shootings are investigated by an outside agency, in this case the Division of Criminal Investigation. Once the division completes its investigation, the report will go to the local district attorney, Koval said.
Wisconsin Circuit Court documents indicate Robinson pleaded guilty in December to an armed robbery that occurred last April.
His mother, Andrea Irwin, painted a different picture of the teen: “My son has never been a violent person, never,” she told told CNN affiliate WKOW. “To die in such a violent way baffles me.”
The police chief refused to comment on Robinson’s past criminal history or run-ins with police.
“I could but I choose not to,” he said at a press conference Saturday.
“I frankly think it is, for our purposes today, wholly inappropriate and I am not going to blemish anyone’s character, particularly someone’s as young as his.”
Because Robinson did not have a weapon, the death spurred memories of other unarmed black men killed by police: Michael Brown in Ferguson, Missouri. Eric Garner in Staten Island, New York.
Over the weekend, protesters filled streets in Madison with a familiar chant following Robinson’s death: “Black lives matter.”
Some of the protesters were members of the Young, Gifted and Black Coalition that was formed last summer after the Michael Brown shooting in Ferguson.
The group wants more reactive policing in African-American neighborhoods, said group member Brandi Grayson.
She said Madison police park on street corners in African-American neighborhoods and wait for something to happen, which leads to residents being hassled. That doesn’t happen in white neighborhoods, she said.
“In light of so much things that have happened not just across the country, but in our own community, it’s understandable that the reaction at the scene and of some of our citizens is extremely volatile, emotional and upsetting,” Chief Koval told CNN affiliate WKOW-TV.
“And we understand that. That’s absolutely appropriate under these circumstances. We would urge, obviously, that everyone exercise restraint.”
Koval said he knows it may be difficult for Madison to move forward after Robinson’s death. He visited the teen’s grandmother over the weekend but was advised by them to not to visit the mother yet. The emotions are still too raw.
“We need to start as any healing or any reconciliation should with an ‘Im sorry,’ and I’ve done that privately, and I’m attempting to do that publicly and that’s the only way we can sort of begin the healing or the rift that may take years if at all to mend,” the police chief said.
“But the effort has to be there. So we have to acknowledge it, we have to own it we have to say we are sorry at the outset for it and then we have to show affirmative steps in moving forward to bring community back into the fold as it were.”
By Holly Yan
CNN’s Rosa Flores, Ralph Ellis, Joe Sutton and Greg Botelho contributed to this report.