The countersuit claims Sgt. Jonathan Mattingly suffered "severe trauma, mental anguish and emotional distress" the night Breonna Taylor was killed

One of the officers involved in the fatal shooting of Breonna Taylor is now suing her boyfriend for "battery, assault and emotional distress" on the night of the March 13 incident.

A new civil suit filed against Kenneth Walker, obtained by PEOPLE, claims that Louisville Police Sgt. Jonathan Mattingly experienced "severe trauma, mental anguish and emotional distress" on the night that Taylor, 26, was killed after officers executed a no-knock search warrant at her apartment.

That night, Walker, a licensed gun-owner, grabbed his firearm and ultimately fired it. He has long maintained that he believed someone was trying to break into the apartment. Kentucky Attorney General Daniel Cameron has asserted Walker's bullet struck an officer, and officers returned fire with 32 shots, six of which struck Taylor.

"Walker's conduct in shooting Mattingly is outrageous, intolerable and offends all accepted standards of decency and morality," reads the lawsuit.

Walker was initially charged with attempted murder for allegedly hitting an officer in the thigh when he fired his gun. Those charges have since been dismissed, and he has since filed a civil suit against the department. Mattingly, via the countersuit, is seeking a jury trial, damages and attorney/medical fees after being shot in the thigh that night.

Breonna Taylor and Kenneth Walker
Breonna Taylor and Kenneth Walker
| Credit: Breonna Taylor/ Instagram; Chris Tuite/ImageSPACE/Shutterstock

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In statement to PEOPLE, Mattingly's attorney Kent Wicker said: "Sgt. Mattingly was shot and nearly killed by Kenneth Walker. He’s entitled to, and should, use the legal process to seek a remedy for the injury that Walker has caused him."

Walker's attorney, Steve Romines, told PEOPLE in a statement, "This is the latest in a cycle of police aggression, deflection of responsibility, and obstruction of the facts in what is an obvious coverup. The counterclaim just brings it full circle. If Kenny can be sued for defending himself, make no mistake, all lawful gun owners’ rights are at risk. And that should scare everyone. We intend to defend Kenny —once again— from baseless charges intended to harm, intimidate, and cover up the events of March 13, 2020.”

Last month, Cameron announced that none of the three police officers involved in the warrant that night would be charged in connection with Taylor's death. Instead, one of the officers, Brett Hankison, was indicted on wanton endangerment charges for allegedly firing bullets that risked injury to persons in an adjacent apartment. Hankinson was also fired from the police department.

RELATED VIDEO: 1 Officer Charged, 2 Cleared in Shooting Death of Breonna Taylor, Grand Jury Decides

In an interview with CBS This Morning co-host Gayle King earlier this month, Walker said the Louisville officers who entered Taylor's apartment that night never announced themselves, contradicting Cameron's assertion that the officers did. He said he's "a million percent sure that nobody identified themselves" outside Taylor's door.

A wrongful death lawsuit filed by Taylor's mother, Tamika Palmer, alleges Walker fired a warning shot as the then-unknown persons breached the front door with a battering ram, and that officers responded by firing into the apartment.

"I never thought it was the police," Walker told King. "Because why would the police be coming here?"

The shooting took place while police were executing a search warrant for an investigation into a suspected drug dealer, who police alleged had once retrieved a package at Taylor's home. But the suspected drug dealer didn't live at Taylor's apartment — and had, in fact, just been arrested at a different location. No drugs were found in Taylor's apartment.

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