Man allegedly Googled 'how to kill your ex's fiancé' before murdering him

The Google logo is seen on a smartphone sitting on a computer keyboard in the background. (Photo by Nicolas Economou/NurPhoto via Getty Images)

A man accused of killing his ex-girlfriend’s fiancé by reportedly typing in a Google search on "how to kill your ex’s fiancé" has been found guilty of murder. 

Jesse Alvarez, 33, was on trial for the murder of 37-year-old Mario Fierro and was found guilty by a jury on Monday. 

Alvarez was convicted of first-degree murder with a special-circumstances allegation of lying in wait to kill Fierro. Alvarez faces life in prison without the possibility of parole when he is sentenced, the San Diego Union-Tribune reported on Monday.

RELATED: Murder-suicide shocks Hawaii: Family of 5 found dead, including 3 children

Alvarez allegedly murdered Fierro at his North Park home in 2021. Fierro was a teacher at Cathedral Catholic High School in San Diego. Fierro was engaged to fellow Cathedral teacher Amy Gembara, Alvarez's ex-girlfriend, KGTV in San Diego reported. 

Prosecutors claimed that the murder of Fierro was premeditated after Alvarez found out in a Facebook post from the school that Gembara was getting engaged. 

Alvarez and Gembara dated off and on from 2015 to 2019. 

On March 7, Alvarez took the stand in his murder trial and testified that he suffered from undiagnosed autism.

He claimed that this was a factor in his obsession with his ex-girlfriend and why he couldn’t interpret social situations, including cues from her that she wanted him to leave her alone. 

According to KNSD-TV in San Diego, Alvarez’s attorney told jurors on Feb. 27 that the man has high-functioning autism and is "extremely religious," two aspects of his life that heavily informed his actions leading up to the shooting.

Citing Alvarez’s lawyer during the trial, KGTV noted that the suspect was outside of Fierro’s home but didn’t plan to shoot him.  Alvarez reportedly was there to meet Fierro, but alleged that Fierro hit him first and that he shot him in self-defense. 

KGTV reported that a crime analyst testified in court on March 7 that prior to the crime, Alvarez searched on Google "how to kill your ex's fiance" and "in California can you shoot someone trying to rob you?"

In the weeks before the shooting, a protection order was issued against Alvarez, and he testified that he attempted to contact Gembara and even accepted a job as a food service employee at the school she worked at.

This story was reported from Washington, D.C.