Man acquitted in murder trial of girlfriend found dead in Phoenix

The trial against a man accused of killing his girlfriend ended Thursday with an acquittal.

A jury found Jon-Christopher Clark not guilty of the second-degree murder charge he faced in the death of Kiera Bergman, according to the Maricopa County Superior Court. Clark was also found not guilty in a tampering with evidence charge against him in the case, according to the court. 

Bergman's body was found Sept. 3, 2018 west of Phoenix after the 19-year-old went missing Aug. 4, 2018. 

"At the end of the trial, we're still not going to know exactly what happened to Kiara but medical examiners will tell you ... their findings and your common sense and all the other witnesses will tell you, that is not an accident. That's murder," a prosecutor said at the Aug. 9 start of the trial. 

Clark, then 23, and Bergman had fights, and the two were seen arguing outside of her apartment the day before her disappearance, according to court documents.

"She's trying to keep me in good spirits because it's my birthday. But I was kind of sad because we weren't really doing anything and then we just started getting into a little bickering, arguing and then she got upset and then she left," Clark told The Arizona Republic shortly after Bergman's disappearance. 

A judge dismissed the case in early 2020, saying prosecutors mishandled Silent Witness records. In January, the trial moved to Pinal County after Bergman's family cited "complications" with a former attorney and the cause being held back in Maricopa County. 

Ultimately, Bergman had an undetermined cause of death. 

Clark's defense attorney said Clark was "cooperative" with investigators since the start and he was the first person to call police when Bergman went missing.

Reach breaking news reporter Jose R. Gonzalez at jose.gonzalez@gannett.com or on Twitter @jrgzztx.

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