19-year-old pleads not guilty in Highlands Ranch STEM school shooting

Devon Erickson appears in court at the Douglas County Courthouse on Wednesday, May 15, 2019, in Castle Rock, Colo. Erickson is one of two students suspected of shooting several classmates in their Colorado charter school. (Joe Amon/The Denver Post via AP, Pool)

CASTLE ROCK | A teenager charged with first-degree murder and other crimes in a suburban Denver school shooting that killed one student and injured eight others pleaded not guilty Thursday.

Devon Erickson, 19, entered his plea in Douglas County District Court in the May shooting at STEM School Highlands Ranch, KMGH-TV reported.

Erickson’s attorneys also entered a notice to introduce possible evidence of his mental condition, and the teen will now be evaluated by a psychiatrist.

Erickson is accused of joining Alec McKinney, 16, in opening fire in a classroom using guns taken from Erickson’s house. Kendrick Castillo, 18, was killed after he and two other students rushed one of the shooters.

Erickson’s lawyers have argued that he was pressured to participate by McKinney, who had befriended him shortly before the shooting.

Last month, a judge found that McKinney should be tried as an adult. He has not yet entered a plea.