A Colorado mother filed a federal lawsuit on Wednesday after police shot and killed her son upon mistaking him for an active shooter.

On the day he was shot in June 2021, Kathleen Boleyn's son, John Hurley, pulled out his gun and went after suspect Ronald Troyke after Troyke was accused of ambushing and fatally shooting Officer Gordon Beesley, court documents obtained by Fox Television Stations have reported.

Troyke, the documents noted, had "a virulent hatred for the police." 

Boleyn filed the complaint in the District Court of Colorado against Arvada Police Department Chief of Police Link Strate and former APD officer Kraig Brownlow.

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Ronald Troyke and Johnny Hurley

A photo of suspected active shooter Ronald Troyke and good Samaritan Johnny Hurley. (Credit: Court documents)

"Instead of concerning himself with self-preservation, Mr. Hurley hurried out the store, drew a concealed carry pistol from his waistband, and ran toward the shooter," according to the lawsuit.

Court documents further said that after shooting him five times and killing him, Hurley took Troyke's AR-15 and removed the magazine.

Seeing Hurley with Troyke's gun, Brownlow then shot and killed the Good Samaritan.

Boleyn's complaint claimed that Brownlow "determined that he needed to immediately eliminate the man in the red T-shirt without even providing a warning."

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Hurley armed with an assault rifle

Photo shows Hurley hunched over while unloading an assault rifle (Credit: Court documents)

"Officer Brownlow saw that Mr. Hurley was completely stationary," documents added. "An active shooter would have likely been moving toward targets."

"If not for Johnny's intervention, there is no telling how many lives Troyke would have claimed," Boleyn's attorneys said in a statement on the suit.

District Attorney Alexis King later cleared Brownlow after the officer claimed that it seemed like Hurley was reloading the rifle or trying to fix it.

King praised Brownlow and said he thought Hurley was a second mass shooter.

Suspect Troyke and Officer Beesley

Troyke raising his weapon toward Officer Beesley. (Credit: Court documents)

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"Based on the District Attorney's findings and after an internal review, the APD found that Officer Brownlow's actions were consistent with APD policy and procedures," Detective David Snelling said in a statement on the lawsuit. "The APD is not considering changes to its actual training or response protocols at this time."

"We stand by every member of the APD. We are confident that any mischaracterizations will be resolved in court," Snelling added.

The Associated Press contributed to this report.