The two students planned the May 2019 attack through social media.
(CN) – A student who pleaded guilty to first-degree murder for the 2019 attack on STEM School Highlands Ranch testified against suspected co-conspirator Devon Erickson on Tuesday at the Douglas County Justice Center in Castle Rock, Colorado.
“The plan was Devon as going to unleash in that room. We both were. At one point, Devon was going to have people line up and then execute them like that,” said Alec McKinney, 18, in court, after pulling his blue surgical mask down over his chin. “The plan was after everyone besides him and myself were dead, he was going to shoot me, and then ultimately, he wanted to come off as the hero.”
According to prosecutors, Erickson shot and killed Castillo — weeks before he was set to graduate — and he and McKinney wounded eight others.
McKinney pleaded guilty to first-degree murder and attempted murder, among other charges, and was sentenced in July 2020 to life in prison plus 38 years. Because he was 16 years old at the time of the shooting, McKinney may be eligible for parole after 40 years.
A transgender male, McKinney said that as a sophomore he said he didn’t know many of the students in room 107 personally but that Erickson told him one of the students hated trans people.
McKinney said he and Erickson were both lonely, felt detached from reality, and were doing cocaine. Through SnapChat and Instagram conversations, they grew close as they planned out the attack.
“I remember it starting as a late-night conversation we had where we were messaging back and forth on SnapChat,” McKinney said. “We were talking about ‘what’s the most messed up thing on your bucket list,’ and I said I wanted to try acid and Devon said he wanted to get away with killing someone.”
McKinney said they started talking about a general attack at the end of April, then narrowed in on committing a mass shooting at their high school.
“The first plan I can remember was he wanted to get everyone into a cabin, say it was a party, and then end up killing those people that were there,” McKinney recalled. “It was narrowed down to Devon disliking the classmates he had in that classroom and saying that was the ideal place to do it, because there were the most people he hated there.”
The court broke before the defense could cross-examine McKinney. During her opening statement, Erickson’s defense attorney Julia Stancil painted him as a confused, impressionable youth, given drugs and manipulated by “puppet master” McKinney.
Erickson faces more than 40 felony charges, including first degree murder. If convicted, he faces a maximum sentence of life in prison without parole since Colorado repealed the death penalty in 2020.
The trial will run daily through June 25.