Kendrick Castillo, 18, was killed, and eight others were wounded when two shooters opened fire at the STEM School in Highlands Ranch, Colo., in 2019

By Chris Harris
June 16, 2021 11:41 AM
Kendrick Castillo
Kendrick Castillo
| Credit: Douglas County Sheriff’s Office

One of the two former students who opened fire at a Colorado high school in 2019, killing hero 18-year-old Kendrick Castillo and injuring eight others, has been convicted of multiple crimes including murder, PEOPLE confirms.

Devon Erickson, 20, will likely spend the rest of his life in prison after jurors Tuesday convicted him on 46 separate criminal counts stemming from the attack at the STEM School in Highlands Ranch - including 31 for attempted murder and three for the first-degree murder of Castillo.

Castillo was hailed a hero in the wake of his death when officials revealed he died protecting his fellow students.

The teen was killed by a single bullet as he charged Erickson, who will be officially sentenced on Sept. 17, court officials told PEOPLE on Wednesday.

Several of the charges carry mandatory minimums, which add up to a life sentence.

Jurors deliberated for less than five hours before returning a guilty verdict on all counts following three weeks of testimony.

Last year, the other shooter, 18-year-old Alec McKinney, pleaded guilty to first-degree murder and other charges for his role in the shooting.

McKinney, who was 16 at the time, was sentenced to life in prison with the possibility of parole after 40 years on the murder charge, as well as 38 more years on the other charges.

Like many parents today, Castillo's father had spoken to the 18-year-old senior about the prospects of a mass shooting at his school.

Kendrick Castillo
| Credit: Maria Castillo/Instagram

John Castillo spoke to NBC News soon after the May 7, 2019, shooting, recalling that fateful conversation, during which he advised the teen: "You don't have to be the hero."

John recounted that Kendrick remained adamant about trying to engage a shooter if it ever came to that.

The father said his late son told him, "'You raised me this way. You raised me to be a good person. That's what I'm doing.'"

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John addressed reporters after the verdict was delivered.

"I'm sure Kendrick was looking down on us today," the father said with tears in his eyes, reports the Denver Post. "This day is justice for him. I never thought I'd be fighting for justice for a crime that should never have happened."

Survivor Mitchell Kraus, one of Kendrick's classmates, also spoke to reporters, saying he hopes the verdict brings some closure.

"We're all part of a family we never wanted to be a part of because this event never should have happened," Kraus explained, according to the Post. "[The shooter] is never going to breathe a breath of free, fresh air ever again."