Updated at 9:21 p.m.

The Chicago Police Board voted at their meeting Thursday night to fire Officer Robert Rialmo for a 2015 on-duty shooting that left two people dead.

Rialmo shot and killed Quintonio LeGrier, 19, and LeGrier’s neighbor, Bettie Jones, 55, while responding to a domestic disturbance call in the West Garfield Park neighborhood. Rialmo has testified he was forced to shoot because LeGrier charged at him with a bat. He admitted he shot Jones on accident.

The police board, which decides on the most serious cases of police misconduct, voted unanimously, with two members abstaining, that Rialmo was not justified in shooting Jones.

“When Officer Rialmo fired his gun in the direction of Bettie Jones, he had the ability to safely reposition himself even farther than he already had from Mr. LeGrier. Had Officer Rialmo done so, he could have neutralized the threat posed by Quintonio LeGrier, and Bettie Jones would be alive today,” the board wrote in its decision. “Officer Rialmo had an obligation to reexamine his options in light of the presence of Ms. Jones and take all reasonable precautions to avoid shooting her.”

The shooting was the first killing by Chicago police after the highly anticipated release of controversial dashcam video showing the police killing of 17-year-old Laquan McDonald. Because of that, many saw the shooting of LeGrier and Jones as the first test of the city’s pledge to improve accountability of officers.

But some police and police supporters believe Rialmo is the victim of political pressure.

Attorney Tim Grace, who represents Rialmo, said they will challenge the board’s decision in Cook County Court, sometime within the next 35 days as the law allows.

Rialmo’s supporters have long maintained that the officer followed department training and policy when he opened fire, and that Jones’ death was a tragedy but should not be blamed on him.

At Thursday’s meeting, Ald. Nicholas Sposato, 38th Ward, blasted the decision as “terrible” and said he was “extremely disappointed.” Sposato said Rialmo was defending himself, and that the board’s decision indicated the board members would rather have attended Rialmo’s funeral than have him defend himself.

Sposato’s remarks drew applause from about half of the audience, including police officers and police union officials. Among the crowd at the meeting to support Rialmo was Officer Anthony LaPalermo, who was Rialmo’s partner the night of the shooting.

Kevin Graham, president of the Chicago Fraternal Order of Police, said the board’s decision sends a “terrible message” to Chicago officers.

“You are telling them that they are on their own. You need to back up the police officers,” Graham said.

The public comment section of Thursday’s meeting was marked with verbal clashes between the mostly-white police officers and the mostly black police reform activists and supporters of Bettie Jones’ family.

Chicago’s Civilian Office of Police Accountability, which was created in the wake of the McDonald video release, investigated the shooting and found Rialmo’s actions unjustified. The agency also found Rialmo lied about elements of the shooting, including the distance between himself and LeGrier when he started shooting.

Chicago Police Superintendent Eddie Johnson opposed Rialmo’s firing but was overruled by the Police Board.

Patrick Smith is a reporter on WBEZ’s Criminal Justice Desk. Follow him @pksmid. Email him at psmith@wbez.org.