By Jeremy Gorner and Gregory Pratt

A Chicago police officer who fatally shot a 19-year-old college student and accidentally killed his neighbor filed a lawsuit against the teenager's estate Friday, arguing the student's actions prompted the shooting and caused the officer "extreme emotional trauma."

Officer Robert Rialmo's lawsuit was filed Friday amid Mayor Rahm Emanuel's efforts to win back public trust in the Chicago Police Department following the release of video last fall of an officer shooting to death 17-year-old Laquan McDonald on Oct. 20, 2014, and other cases of alleged police misconduct.

Rialmo's lawsuit provides the officer's first public account of the Dec. 26 shooting in the West Garfield Park neighborhood. It says Rialmo opened fire after Quintonio LeGrier twice swung a bat at his head at close range, and LeGrier was shot when Rialmo saw him raising the bat again and thought LeGrier could kill him if LeGrier hit him in the head with the bat.

LeGrier's father, Antonio LeGrier, had filed a wrongful death lawsuit saying his son wasn't a threat, and Rialmo's lawsuit, which asks for damages of more than $10 million, is a countersuit in that case. Rialmo also fatally shot Antonio LeGrier's neighbor Bettie Jones, 55, in the confrontation, but police have said her death was accidental.

Antonio LeGrier's attorney, Basileios Foutris, was incredulous at what he called the officer's "temerity" in suing the college student's grieving family. Foutris said the lawsuit was "outlandish."

"After this coward shot a teenager in the back ... he has the temerity to sue him? That's a new low for the Chicago Police Department," Foutris said.

Rialmo's lawyer, Joel Brodsky, said Saturday that his client is going through a grieving process that officers experience whenever they fatally shoot someone.

"He's got this extra added burden (with) the death of Jones," Brodsky said. "He's going through what I would call the normal grieving process for someone who is forced to take a human life."

Brodsky said there's been a presumption that his client did something wrong when he opened fire on LeGrier and the lawsuit was an opportunity to get Rialmo's side of the story out there, because it hasn't been disclosed officially.

Rialmo was shifted to 30 days of mandatory paid administrative duties under a policy implemented after the LeGrier shooting. Officers who are involved in shootings are not relieved of their police powers or accused of any wrongdoing by the department.

Last week, interim police Superintendent John Escalante told the Tribune that Rialmo's administrative duties were extended indefinitely.

The lawsuit filed Friday says Quintonio LeGrier confronted Rialmo after his father's downstairs neighbor, Bettie Jones, answered the front door of the frame two-flat in the 4700 block of West Erie Street and then moved to go back into her apartment.

After Rialmo stepped into the front door of the building, LeGrier came "barging" out the front door of the second-floor apartment, holding a baseball bat in his right hand, according to the lawsuit. Rialmo had been standing in the front doorway, and when LeGrier got downstairs, he "took a full swing" at the officer, "missing (his head) by inches, but getting close enough for Officer Rialmo to feel the movement of air as the bat passed in front of his face."

Rialmo backed onto the front porch near the top of the front stairs, and "repeatedly shouted orders for LeGrier to drop the bat," but the teenager instead followed him onto the porch and took another swing at Rialmo, the lawsuit states. Rialmo, who was still shouting for LeGrier to drop the bat and had his gun in his holster, then backed down to the bottom of the steps.

LeGrier stood "with the baseball bat cocked back over his right shoulder with a two-handed grip, approximately 3 feet above Officer Rialmo and approximately 3 to 4 feet from where Officer Rialmo was standing on the bottom step of the front porch to the building. Officer Rialmo feared that LeGrier would strike him in the head with the baseball bat so hard that it would kill him," the lawsuit states.

"Rialmo reasonably believed that if he did not use deadly force against LeGrier, that LeGrier would kill him. Officer Rialmo drew his handgun from its holster, and starting to fire from holster level, fired eight rounds at LeGrier from his 9 mm Smith & Wesson handgun, which holds 18 rounds, in approximately two and a half seconds," the lawsuit states.

LeGrier was shot on the left side of his chest, the lower left side of his back, the right buttock, the left arm and suffered graze wounds to his chest and right shoulder, according to LeGrier's autopsy report. Jones died of a single gunshot wound to the chest, Cook County medical examiner records show.

The "fourth round that Officer Rialmo fired passed through LeGrier and struck Bettie Jones, who unbeknownst to Officer Rialmo, was standing in the front doorway to the building ... behind LeGrier and partially exposed to any gunfire that might pass through LeGrier," the lawsuit states.

"The fact that LeGrier's actions ... forced Officer Rialmo to end LeGrier's life, and to accidentally take the innocent life of Bettie Jones, has caused, and will continue to cause, Officer Rialmo to suffer extreme emotional trauma," the lawsuit states.

Rialmo's account contrasts with that given in the lawsuits brought by the LeGrier and Jones families.

According to the lawsuit filed by Antonio LeGrier, his son was inside the building when he was shot and Rialmo was outside. The suit also alleges the younger LeGrier did not present an immediate threat to anyone before the shooting, including any police officers.

Quintonio LeGrier also wasn't doing anything illegal immediately before or after he was shot, according to that suit.

In the lawsuit filed by the Joneses, "Bettie Ruth Jones faced a hail of bullets being fired by an on-duty Chicago Police Department officer at and in the direction of her home ... with bullets going through the doorway, and through the walls of the home..."

One of the lawyers for Jones' family has said Rialmo was about 20 feet away when he opened fire.

Neither the Chicago Police Department nor the Independent Police Review Authority, the city agency that investigates police-involved shootings, have officially released Rialmo's version of events, citing the ongoing investigation.

But the Tribune, citing a law enforcement source, first reported a few days after the shooting that Rialmo told investigators that the teen had swung at him with a baseball bat, prompting the officer to shoot LeGrier.

On Saturday, Brodsky said that relatives of those fatally shot by the police, such as the LeGrier family, are looking for ways to get paid after the city settled the Laquan McDonald shooting case last year for $5 million.

"Ever since the McDonald payoff, people are treating officer-involved confrontations like a lottery ticket and they're waiting to cash it in," Brodsky said.

Chicago Tribune reporter Liam Ford and the Associated Press contributed.

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