Jesse Alvarez: California man convicted of murdering ex-girlfriend's fiance after he searched online 'how to shoot someone'

On February 1, 2021, Jesse Alvarez fatally shot Mario Fierro, 37, as the latter was leaving for work at Cathedral Catholic High School, where he served as a beloved teacher
PUBLISHED MAR 13, 2024
Jesse Alvarez claimed that he shot Fierro in self-defense during his testimony (Philadelphia Police Department and Catholic Community Foundation of San Diego)
Jesse Alvarez claimed that he shot Fierro in self-defense during his testimony (Philadelphia Police Department and Catholic Community Foundation of San Diego)

Warning: This article contains a recollection of crime and can be triggering to some, readers’ discretion advised.

SAN DIEGO, CALIFORNIA: A 33-year-old man was convicted of murdering his ex-girlfriend's fiance in San Diego, California, in a jealous rage. 

On February 1, 2021, Jesse Alvarez fatally shot Mario Fierro, 37, as the latter was leaving for work at Cathedral Catholic High School, where he served as a beloved teacher alongside his fiancee, Law&Crime reported.

During the trial, Alvarez claimed he shot the victim in self-defense, however, prosecutors presented compelling evidence, including his internet search history, which showed queries such as "how to shoot someone with a 9mm Glock," before the murder.

What did Jesse Alvarez claim during the testimony?

During the trial, Jesse Alvarez told the jury that his feelings for his ex-girlfriend had grown into an unhealthy obsession after she ended their three-and-a-half-year relationship. 

His anger intensified upon discovering via social media that his ex-girlfriend and her fiance worked at a school together and were engaged. 

Alvarez testified that he shot Fierro in self-defense. 

(NBC7/Screengrab)
Jesse Alvarez told the jury that his feelings for his ex-girlfriend had grown into an unhealthy obsession after she ended their three-and-a-half-year relationship (NBC7/Screengrab)

However, this defense was challenged by the fact that Fierro was shot six times, including four times in the head. 

Alvarez recounted that he had gone to Fierro's residence to have a conversation.

Alvarez said, "He rushed at me, and I was completely taken aback. He started trying to punch me, He tried to seize the firearm from my hand, and we were wrestling over it. And he started to point it towards my direction. And then he got his fingers around the trigger, and he pulled it.”  

During this altercation, Alvarez allegedly fired a shot, causing Fierro to fall to his knees. Fierro then regained his footing and continued the attack, prompting Alvarez to open fire again, the accused claimed.

What did prosecutors in the case say?

Mario Fierro ( Catholic Community Foundation of San Diego)
McCarthy asserted, "Mr. Fierro had no idea the defendant was there and no idea of his presence ( Catholic Community Foundation of San Diego)

Following Alvarez's testimony, prosecutors presented evidence against him, highlighting the Google searches on his computer after learning about the engagement. 

These searches included phrases such as "how to commit the perfect murder," "how to shoot someone with a 9mm Glock," and "how to hire a hitman." 

In response, Alvarez attempted to dismiss these searches as mere fantasies. 

His defense attorney, Peter Blair, sought to raise doubts about the premeditation of the murder, stating, "If this is premeditated, then he’s just shooting him right away. He’s not trying to talk to him, not trying to make conversation," 

However, Deputy District Attorney Ramona McCarthy argued that Alvarez was fully aware of his actions and that this was not a case of self-defense. 

McCarthy asserted, "Mr Fierro had no idea the defendant was there and no idea of his presence — had no idea the defendant waited almost an hour for him and watched him and waited right until he had his back to him. He’s a coward." 

Alvarez's sentencing has reportedly been set for May 10, 2024.

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