ADAMS COUNTY, Colorado — A lawsuit filed in Adams County court seeks criminal charges against three police investigators and a prosecutor – accusing them of ignoring for a year sexual assault allegations against a key witness in the murder of a sheriff’s deputy, 9Wants to Know has learned.

That case, which involves allegations of repeated sexual assaults on a teenage girl by one of her teachers, is at the center of the sequence of events that ended in the January 2018 killing of Adams County sheriff’s deputy Heath Gumm, according to the suit — a copy of which was obtained Thursday by 9Wants to Know.

Photos of Adams County Deputy Heath Gumm shown during his funeral. The 31-year-old was shot and killed on Jan. 24 while responding to an assault call.

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It is not clear whether the suit will have any effect on the prosecution of 23-year-old Dreion Dearing, who is scheduled to go on trial in September on four counts of first-degree murder, two counts of burglary, and charges of weapons possession by a previous offender and assault.

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Adams County District Attorney Dave Young is seeking the death penalty against Dearing.

The suit was filed against Young on behalf of a young woman who alleged that she was repeatedly sexually assaulted – beginning when she was 14 – by one of her teachers at the Denver School of Innovation and Sustainable Design. The suit was filed in an effort to compel Young to prosecute three Adams County sheriff’s investigators and one of his deputy district attorneys on charges of official misconduct and failure to report child abuse. 

Sue Lindsay, spokeswoman for Young’s office, said she had not seen the suit and could not comment.

“We don’t comment on pending litigation,” said senior deputy Mike Kaiser, a spokesman for the Adams County Sheriff’s Office.

Gumm was shot to death during the investigation of a burglary and assault at the home of Peter Aquino, located at 8771 Dawson St. in unincorporated Adams County.

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Will Jones, spokesman for Denver Public Schools, said Aquino was a teacher for the district during the 2013-2014 school year and then worked as a contractor at the Denver School of Innovation and Sustainable Design from Dec. 10, 2015 to Nov. 7, 2017. According to the suit, Aquino was a “poetry advisor” at the school, which is located at 840 E. 14th Ave. in Denver.

The suit alleges that Aquino repeatedly sexually assaulted one of his students, beginning when she was 14 years old, and that she and others went to his home and attacked him on Jan. 24, 2018. Among them, according to the suit, was Dearing, who is the girl’s cousin.

Gumm was shot to death as deputies searched through yards in the area looking for suspects.

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According to the suit, Adams County sheriff’s investigators Liliana Cano, Luis Hernandez, Mark Faulhaber and deputy district attorney Jess Redman all learned of the allegations against Aquino during their investigation of Gumm’s death, but did nothing.

According to court documents, during an interview with the investigators, Aquino confessed to having had sex with an underage student. But the investigators told him they didn't plan to pursue it.

“So all we’re interested in is our end – and that’s the murder,” Hernandez told him, according to the suit.

“Our intention isn’t to screw you over. Our intention is to get these people that were involved in the death of one of our officers,” Cano said to Aquino during the interview, according to the suit.

According to the suit, the girl was in Aquino’s poetry class, and at some point he allegedly learned that the girl had been a prior victim of sexual assault.

They had a sexual encounter in December 2015. The girl was 14 and Aquino was 24 at the time, the suit said.

They also exchanged sexually explicit photographs and began having sex in his car and in hotel rooms, according to the suit.

On Jan. 20, 2018, according to the suit, Aquino’s girlfriend learned of the assaults, and she started harassing and confronting the girl.

It was four days later that the girl and others – including Dearing – allegedly went to Aquino’s home and assaulted him and others, sparking the search that ended in Gumm’s death. 

The alleged series of sexual assaults wasn’t reported until March 6, 2018, after a social worker in Arapahoe County learned of them and called Wheat Ridge police. That was more than a month after Gumm's death.

Aquino was arrested Feb. 20 of this year – more than a year after he allegedly confessed to the investigators that he’d sexually assaulted the girl.

He faces three counts of sexual assault on a child and two counts of sexual exploitation of a child.

The lawsuit seeks the appointment of a special prosecutor to file charges of official misconduct and failure to report child abuse – both misdemeanors – “as well as other charges that this court deems appropriate” against Hernandez, Cano, Faulhaber and Redman. 

Contact 9NEWS reporter Kevin Vaughan with tips about this or any story: kevin.vaughan@9news.com or 303-871-1862.

9Wants to Know producer Zack Newman contributed to this report. 

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