A teenager who killed four students at his Michigan high school in 2021 was like a “feral child,” deeply neglected by his parents during crucial years and mentally ill, a psychologist testified Tuesday at a hearing to determine if the mass shooter will get a life prison sentence.

Ethan Crumbley’s lawyers also played disturbing videos from jail showing the 17-year-old in deep distress as deputies restrained him while he wailed. In one incident, his head is completely covered with a hood. No dates were disclosed.

“Why didn’t you stop it? I’m sorry. ... Stop it, God, why?” he said. “A number of my clients have had issues with the law,” said King, who has testified in many homicide cases. “Through psychotherapy and support, they’ve been able to make progress. ... Ethan’s brain is still maturing.”

Crumbley pleaded guilty to murder, terrorism and other charges in a shooting that killed four students and wounded seven others at Oxford High School, about 40 miles (64 kilometers) north of Detroit.

Because of his age — 15 at the time — the shooter can’t automatically be a given life sentence. Oakland County Judge Kwame Rowe first must consider the shooter’s maturity, mental health, unstable family life and other factors set by the U.S. Supreme Court.

He still can order a life sentence, but it would be a rare outcome for a teen. Crumbley otherwise would face a minimum sentence somewhere between 25 years and 40 years in prison, followed by eligibility for parole. A decision isn’t expected Tuesday, the third and likely final day of the hearing

King said he spent more than 20 hours with the shooter during several meetings, interviewing him and running him through a series of psychological tests. He also reviewed the teen’s dark journal entries and text messages.

King disclosed for the first time that the boy believed that a gun was going to be found in his backpack on the day of the shooting when he was sent to the office for drawing violent images in class.