STEM School Shooter Testifies During Accused Accomplice’s Trial

A convicted school shooter gave his first public testimony on Tuesday, June 8, during the murder trial of his accused accomplice. The May 7, 2019, shooting at STEM School Highlands Ranch in Highlands Ranch, Colo., left one student dead and eight injured.

During the ongoing murder trial of suspect Devon Erickson, 20, convicted co-defendant Alec McKinney, 18, gave insight into the planning of the attack. McKinney pled guilty to first-degree murder and over a dozen other related charges in February 2020 and is currently serving a life sentence plus 38 years in prison.

During his testimony, McKinney told a Douglas County District Court jury that he and Erickson discussed plans for weeks and explained how the classroom in question was targeted. “It was narrowed down to Devon disliking the classmates he had in that classroom,” said McKinney. “It was the most ideal place because it had the most people he hated, that they would be there at the same time.”

McKinney said that he and Erickson had lists of students that they didn’t like and planned to target. McKinney discussed how they procured the firearms used in the attack and said that Erickson had considered plans of lining his classmates up against the wall and executing them.

McKinney testified that the plan was for Erickson to kill McKinney at the end of the shooting: “The end of the plan, after everyone was dead, he was going to shoot me to make it look like he attempted to save everyone, and ultimately he wanted to come off as the hero,” said McKinney. McKinney said that he agreed to this plan because “I didn’t really care about my life, nor what was said of me after I was gone,” he said on Tuesday.

McKinney said that in the weeks leading up to the shooting, he and Erickson researched the Columbine High School shooting and its perpetrators. He said they found the website of an 18-year-old Florida woman who was obsessed with the Columbine shooting and had recently died of a self-inflicted gunshot wound.

“After looking through her public website, we thought we related to the things she was saying there,” McKinney said. “We both related to how all those people were feeling. A detachment from reality, and we felt that; feeling lonely; frustrated with school and peers.”

“Devon and myself were not in a good place in that time, mentally,” McKinney said on Tuesday.

McKinney, who was 16 at the time of the STEM School Highlands Ranch shooting, was tried as a juvenile and is eligible for parole after 40 years. Erickson, who was 18 during the shooting, faces life in prison without the possibility of parole. He faces two first-degree felony murder charges and more than 40 other associated felonies.

About the Author

Matt Jones is senior editor of Spaces4Learning and Campus Security and Life Safety. He can be reached at


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