As a police detective, Bryan Gibbins interviewed underage sexual assault victims to try to bring criminal cases against their alleged abusers.

He also had sex with one such underage victim, according to records related to his recent arrest.

That basically eliminates Gibbins, 38, as a prosecution witness at future trials of anyone he’s investigated, say legal experts. What that means for those criminal prosecutions depends on what Gibbins’ role was, said Toby Shook, a Dallas defense attorney and former state prosecutor. But it is generally not good news for the state, he said.

“The prosecution is going to have to work harder to work around him,” Shook said. “Depending on his role, it may cause the state to change their plea offer or come to some resolution they hadn’t intended.”

The Denton County district attorney’s office did not respond Friday to a call about what possible impact the Gibbins case might have on active cases he worked.

“The DA’s office will have no choice but to review all of Gibbins’ cases,” said Derek Staub, a Dallas defense attorney. “The office will need to confirm that the facts are true and correct.”

Bryan Gibbins (Denton County jail)

Gibbins worked for the Lewisville Police Department from 2006 until last July.

The most high-profile case he investigated involved sexual abuse allegations against Lauren Kavanaugh, whose story of horrific abuse by her mother and stepfather as a child became an eight-part series in The Dallas Morning News titled, “The Girl in the Closet.” Her mother and stepfather, Barbara and Kenneth Atkinson, are serving life sentences in Texas prisons.

Kavanaugh, 25, was herself charged in March 2019 in Denton County with three counts of child sexual assault after confessing to Gibbins about having sex with a 14-year-old girl, according to court records. Gibbins wrote in an arrest warrant affidavit that the victim had met Kavanaugh through a Facebook fan page in 2017 and then reconnected in summer 2018, ultimately leading to Kavanaugh moving in with the girl’s family. She was arrested in December 2018.

Gibbins began his own sexual relationship with an underage girl not long after that, according to a search warrant affidavit in his case.

The relationship lasted from early 2019 until Jan. 9 of this year, the affidavit said. The victim was 15 when her sexual relationship with Gibbins began, police said. Gibbins, who was working in the department’s crimes against children unit, had been assigned to a case in which the girl was the victim, according to the affidavit.

Investigators found nude pictures of the victim as well as her clothing during a search of Gibbins’ apartment, the affidavit says.

Questions linger

Shook said the former detective’s arrest does not mean the state cannot prosecute Kavanaugh.

But prosecutors won’t be able to call him as a witness in the upcoming Kavanaugh trial, he said. And prosecutors will try to keep the jury from learning about Gibbins’ arrest, Shook said.

Kavanaugh’s attorney could not be reached Friday for comment.

Tim Powers, an attorney for Gibbins, said on Friday that he looks forward to his client being vindicated at trial.

“We believe 100% in his innocence,” Powers said, adding that his $4 million bail was set unreasonably high.

Gibbins’ closed cases should not be affected by the current allegations against him, Shook said.

However, if defense attorneys in those closed cases can prove that Gibbins had improper relationships with other victims and perhaps “manipulated them into saying something,” that could be grounds for reopening them, Shook said.

The arrest of the former detective, he said, “raises questions about how long he’s been doing this.”

Staub said the Denton DA will have to file court papers informing defendants in pending cases about Gibbins’ alleged actions.

“Then, defense attorneys will use this to either get a dismissal or lesser punishment,” he said. “Gibbins’ word now means nothing.”

Gibbins would often take his victim to and from school in his police vehicle, and he communicated with her through Snapchat, the affidavit said. She said Gibbins sent her nude pictures of himself from the bathroom of the home he shared with his wife and later, from the bathroom of an apartment he moved into, the affidavit states.

Gibbins and the victim agreed to become “exclusive” on March 30, the affidavit says. Around that time, Gibbins separated from his wife and moved into the victim’s apartment complex, according to the document.

In the affidavit, the victim said that Gibbins had her perform sex acts on him before school in the parking lot of a local Target store. Sometime in June, Gibbins came to her apartment and they had sex — the first instance of intercourse between the two — while he was on duty, the affidavit states.