CASTLE ROCK, Colo. -- Prosecutors have enough evidence for a teenager to be tried in the STEM School Highlands Ranch shooting that killed one of his classmates and wounded eight others, a judge said Wednesday.
Judge Theresa Slade ruled Devon Erickson, 19, should be tried on more than 40 criminal charges, including murder and attempted murder, in connection with the May 7 attack.
Previously released court records suggest the attack might have been planned by Erickson's friend, Alec McKinney.
Written summaries of police interviews with the two suspected shooters portray McKinney as enlisting Erickson in a plan to kill students who bullied McKinney, who identifies as male.
McKinney, 16, has a preliminary hearing scheduled in November on the same charges. His attorneys are seeking to move his case to juvenile court.
During a two-day preliminary hearing, the judge heard testimony that the pair got their guns by breaking into a safe at Erickson's house the day of the attack.
Erickson's lawyers stressed that McKinney pressured him to participate.
They pointed to a text McKinney sent him shortly before the shooting saying that he couldn't launch the attack alone and that he threatened to harm Erickson, saying he would "(expletive) you up."
McKinney texted afterward, "We have it all planned out," and Erickson replied, "Go now," prosecutors said.
Nearly simultaneously, surveillance video shows students near the classroom where the shooting happened scattering in reaction, 18th Judicial District Attorney George Brauchler said.
The classroom was dark, showing the movie "The Princess Bride."
Even if Erickson's job was only to make sure no one left the room through one classroom door as McKinney fired from another, Brauchler said Erickson showed total disregard for life by attempting to help his friend kill as many people as possible.
"At the end of the day, this is much like, in for a penny, in for a pound," Brauchler said.
Erickson and McKinney are charged with murder and attempted murder in the shooting that killed Kendrick Castillo, 18, one of three students who rushed Erickson after he pulled out his gun in the classroom.
They have not entered pleas to the charges yet.
Another student tackled McKinney on the other side of the room, but he was able to get away before being handcuffed by the school's armed security guard.
Erickson sat next to his lawyers in court wearing a red jail uniform and a shackle around his waist.
He smiled at least once at a small group of people seated on his side of a courtroom packed mostly with members of the school community, including Castillo's parents in the front row. Underneath his button-down shirt, his father wore a T-shirt with his son's photo on it, which he is not allowed to display in court.
While Erickson told investigators that he fired accidentally after being charged and then surrendered his gun, one of the students who rushed him, Brendan Bialy, said he was only able to pry the gun away after punching him several times.
Three empty bullet casings were found on the ground near Erickson and one empty one in the gun after it got stuck inside. That prevented Erickson from firing more bullets, Brauchler said.
The defense argued that two Snapchat videos of McKinney and Erickson in the hours before the shooting -- one showing McKinney yelling at Erickson to get the safe open, with the ax visible at the bottom of the screen, and another of McKinney yelling at him to use cocaine -- show the pressure he was under.AlertMe