PONTIAC, Mich. — A judge sentenced the parents of a Michigan school shooter to at least 10 years in prison Tuesday for failing to take steps that could have prevented a “runaway train” — the killing of four students in 2021.

Jennifer and James Crumbley are the first parents convicted in a U.S. mass school shooting. They were found guilty of involuntary manslaughter after prosecutors presented evidence of an unsecured gun at home and indifference toward the teen’s mental health.

Ethan Crumbley drew dark images of a gun, a bullet and a wounded man on a math assignment, accompanied by despondent phrases. Staff at Oxford High School did not demand that he go home but were surprised when the Crumbleys didn’t volunteer it during a brief meeting.

Later that day, on Nov. 30, 2021, the 15-year-old pulled a handgun from his backpack and began shooting. Ethan, now 17, is serving a life sentence for murder and other crimes.

“These convictions are not about poor parenting,” Judge Cheryl Matthews said. “These convictions confirm repeated acts, or lack of acts, that could have halted an oncoming runaway train.

“About repeatedly ignoring things that would make a reasonable person feel the hair on the back of their neck stand up,” the judge said. “Opportunity knocked over and over again — louder and louder — and was ignored. No one answered.”

Defense attorneys asked that the Crumbleys be spared a prison term, noting they have already served nearly 2 1/2 years in jail after failing to meet a $500,000 bond after their arrest.

The Crumbleys will be eligible for parole after serving 10 years in custody and will get credit for the jail time. If parole is denied, they can't be held longer than 15 years.

Before sentencing, family members of the slain students asked the judge for a 10-year term, condemning the parents as failures whose selfishness led to four deaths and a community tragedy.

“The blood of our children is on your hands, too,” said Craig Shilling, wearing a hoodie with the image of son Justin Shilling on his chest.

Nicole Beausoleil, the mother of Madisyn Baldwin, recalled simple things she enjoyed doing for her daughter, such as scheduling an oil change for her car or helping choose senior year classes.

“While you were purchasing a gun for your son and leaving it unlocked, I was helping her finish her college essays,” Beausoleil told the Crumbleys.

Five deputies in the courtroom stood watch over the couple and more lined the walls.

Prosecutors said simple acts by both parents could have stopped the catastrophe.

“Consider the devastating impact of their gross negligence that was foreseeable,” prosecutor Karen McDonald told the judge.

She then quoted the grim handwritten lines on Ethan's math paper: “Help me. Blood everywhere. The world is dead.”

“All the while a 9 millimeter (gun) had just been purchased for him and 50 rounds of ammunition,” McDonald said.

The couple had separate trials in Oakland County court, 40 miles north of Detroit. Jurors saw the teen's violent drawing on his school assignment and heard testimony about the crucial hours before the attack.

Ethan had told a counselor he was sad — a grandmother had died and his only friend suddenly had moved away — but said the drawing only reflected his interest in creating video games.

The Crumbleys attended a meeting at the school that lasted less than 15 minutes. They did not mention that the gun resembled one James Crumbley had purchased just four days earlier — a Sig Sauer 9 mm that Ethan had described on social media as his “beauty.”

His parents didn’t take him home, choosing instead to return to work and accepting a list of mental health providers. School staff said Ethan could stay on campus. A counselor, Shawn Hopkins, said he believed it would be safer for the boy than possibly being alone at home.

No one, however, checked Ethan’s backpack. He pulled the gun out later that day and killed four students — Tate Myre, Hana St. Juliana, Shilling and Baldwin — and wounded seven other people.

Before being sentenced, James Crumbley, 47, stood and insisted he did not know his son was deeply troubled.

“My heart is really broken for everybody involved. ... I have cried for you and the loss of your children more times than I can count,” he said.

Jennifer Crumbley, 46, began her remarks by expressing her “deepest sorrow” about the shooting. She also said her comment at her trial about not doing anything differently was “completely misunderstood.”

“My son did seem so normal. I didn't have a reason to do anything different,” Jennifer Crumbley said. “With the benefit of hindsight and information I have now, my answer would be drastically different.”

She blamed the school for not giving her the “bigger picture” about Ethan: sleeping in class, watching a video of a mass shooting, writing negative thoughts about his family.

“The prosecution has tried to mold us into the type of parents society wants to believe are so horrible only a school or mass shooter could be bred from,” Jennifer Crumbley said. “We were good parents. We were the average family.”

During the trials, there was no testimony from specialists about Ethan's state of mind. But the judge, over defense objections, allowed the jury to see excerpts from his journal.

“I have zero help for my mental problems and it’s causing me to shoot up the ... school,” he wrote. “I want help but my parents don’t listen to me so I can’t get any help.”

Asked about Ethan reporting hallucinations months before the shooting, Jennifer Crumbley told jurors he was simply “messing around.”

At the close of James Crumbley’s trial, the prosecutor demonstrated how a cable lock, found in a package at home, could have secured the gun.

“Ten seconds,” McDonald said, “of the easiest, simplest thing.”