Action against Roy Oliver for flouting department policies in the killing of African-American Jordan Edwards.

Police in suburban Dallas fired the officer who shot and killed a 15-year-old African-American boy riding in a vehicle leaving a chaotic house party, taking the swift action demanded by the boy’s family and protesters linking the case to other deaths of African-Americans at the hands of law enforcement.

The Balch Springs, Texas, officer, identified as Roy Oliver, was terminated from duty for violating department policies in the shooting to death of Jordan Edwards, Police Chief Jonathan Haber said.

The officer fatally shot Edwards, a high school freshman leaving a party with his two brothers and two other teenagers on Saturday night. Police at the scene to investigate an under-age drinking complaint spotted the vehicle leaving. Mr. Oliver opened fire as the teenagers were driving away.

Shots from his rifle pierced the front side passenger window, hitting Edwards in the front seat, according to Edwards’ family attorneys, Lee Merritt and Jasmine Crockett. His 16-year-old brother was driving.

Aggressive reversing? no

Police originally said the teenagers’ vehicle was reversing “in an aggressive manner” toward officers, but Mr. Haber said on Monday that video taken at the scene proved the vehicle was actually driving away.

The police department’s latest statement, released Tuesday night, says officers entering the house heard gunshots ring out during a “chaotic scene with numerous people running away from the location.” As officers exited the house, they encountered the vehicle backing out onto a main road and driving away despite their attempts to tell the driver to stop, the new statement said.

It is homicide

The Dallas County medical examiner ruled Edwards’ death a homicide.

Thousands of Facebook and Twitter users have posted about the case in recent days with the hashtag “{nldr}jordanedwards,” some comparing his death to other police shootings of young black men, such as 12-year-old Tamir Rice in Cleveland who was fatally shot in November 2014 as he held a pellet gun.

Edwards’ family had called for the officer to be fired and criminally charged. Both the attorneys have credited Haber for correcting the mistaken statement and moving quickly to fire Mr. Oliver.

“No other city has moved at the rate Balch Springs has,” Ms. Crockett told The Associated Press on Tuesday night. “It’s just unbelievable. It’s absolutely unbelievable that a department did what a department should do.”

But a family statement released Tuesday night called for disciplinary action against other officers who “extended this nightmare for those children.”

Traumatised family

“Our family is working hard to deal with both the loss of our beloved Jordan and the lingering trauma it has caused our boys,” the family statement said.

Friends have described Edwards as a good student and popular athlete. Edwards and the four people with him decided to leave what was becoming an unruly party as they heard gunshots ring out and police were arriving, Merritt said, citing what witnesses had told lawyers.

As they drove away from the party, Ms. Crockett said, the brother driving the vehicle heard multiple gunshots that were close enough to leave his ears ringing. It took a few moments before the people inside in the car noticed Edwards slumped over, she said. They couldn’t tell if he was already dead.

The brother, who was driving pulled over and tried to motion to police for help, she said. Instead, Ms. Crockett said, he was detained and handcuffed. Ms. Crockett said the driver wasn’t formally arrested, but a separate statement from the family released through Merritt says the two brothers were arrested.

Use-of-force policy

Based on what the video captured, Mr. Haber said previously that he questioned whether what he saw was “consistent with the policies and core values” of his department. Mr. Haber wouldn’t say what problems he saw, but Balch Springs’ official use-of-force policy encourages officers facing an oncoming vehicle to “attempt to move out of its path, if possible, instead of discharging a firearm at it or any of its occupants.” The video has not been released.