A Michigan jury convicted a school shooter’s mother of involuntary manslaughter Tuesday in the killings of four students in 2021, making her the first parent in the U.S. to be held responsible for a child carrying out a mass school attack.

Prosecutors say Jennifer Crumbley had a duty under state law to prevent her son, who was 15 at the time, from harming others. She was accused of failing to secure a gun and ammunition at home and failing to get help to support Ethan Crumbley’s mental health.

The four guilty verdicts — one for each student slain at Oxford High School — were returned after roughly 11 hours of deliberations. Jennifer Crumbley, 45, looked down and shook her head slightly as each juror was polled after the verdicts were read.

On her way out of the courtroom, prosecutor Karen McDonald hugged relatives of victims Justin Shilling and Madisyn Baldwin.

“Thank you,” a man whispered to her.

Jennifer and James Crumbley were the first parents in the U.S. to be charged in a mass school shooting committed by their child. James Crumbley faces trial in March.

“The cries have been heard, and I feel this verdict is gonna echo throughout every household in the country,” Justin’s father, Craig Shilling, said outside the courtroom.

“I feel it’s necessary, and I’m happy with the verdict. It’s still a sad situation to be in. It’s gotta stop. It’s an accountability, and this is what we’ve been asking for for a long time now,” Shilling said.

A gag order by the judge prevented McDonald and defense attorney Shannon Smith from speaking to reporters.

On the morning of Nov. 30, 2021, school staff members were concerned about a violent drawing of a gun, bullet and wounded man, accompanied by desperate phrases, on Ethan Crumbley’s math assignment. His parents were called to the school for a meeting, but they didn’t take the boy home.

A few hours later, Ethan Crumbley pulled a handgun from his backpack and shot 10 students and a teacher. No one had checked the backpack.

Outside the courthouse, the jury forewoman, who declined to give her name, said jurors were influenced by evidence that Jennifer Crumbley was the last adult to possess the gun. That “really hammered it home,” she told reporters.

Indeed, the jury saw images of Jennifer Crumbley leaving the shooting range with the gun in a box.

“You saw your son shoot the last practice round before the (school) shooting on Nov. 30. You saw how he stood. ... He knew how to use the gun,” assistant prosecutor Marc Keast said while cross-examining the mother last week.

In her closing argument Friday, McDonald said she filed the unprecedented charges because of the “unique, egregious” facts leading up to the massacre. School officials insisted they would not have agreed to keep Ethan Crumbley on campus that day if the parents had shared information about the new gun, which the boy on social media called his “beauty.”

The words with the disturbing drawing said: “The thoughts won’t stop. Help me. The world is dead. My life is useless.”

“He literally drew a picture of what he was going to do,” McDonald said. “It says, ‘Help me.’”

Besides 17-year-old Justin Shilling and 17-year old Madisyn Baldwin, Hana St. Juliana, 14, and Tate Myre, 16, were also killed. Seven people were wounded.

Ethan Crumbley, now 17, pleaded guilty to murder and terrorism and is serving a life sentence.