CASTLE ROCK, Colo. (AP/CBS4) — One of the two Colorado teenagers charged in the STEM School Highlands Ranch Shooting is in court Monday for a judge to determine whether prosecutors have enough evidence to go to trial. A judge also is expected to hear arguments on whether 16-year-old Alec McKinney should be tried as an adult for the May 7 attack.

Alec McKinney (credit: Instagram)

The shooting at STEM School Highlands Ranch killed one student and injured eight others. Kendrick Castillo, 18, was killed in the shooting after he and two other students rushed one of the shooters who opened fire in the classroom.

(Photo by Tom Cooper/Getty Images)

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McKinney’s probable cause hearing is expected to last up to a week.

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In September, a judge found that McKinney’s alleged accomplice, 19-year-old Devon Erickson, could be prosecuted on 44 charges that include murder and attempted murder.

Devon Erickson (credit: CBS)

STORY NOTE: McKinney is a female who identifies as male and prefers to be called Alec.

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(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)