Jennifer Crumbley has been found guilty in a landmark decision.

On Feb. 6, the mother of Ethan Crumbley—the Michigan teen who perpetrated a deadly school shooting in 2021—became the first parent to be held criminally responsible for a mass shooting carried out by their child. Jennifer, 45, was found guilty by a jury on four charges of involuntary manslaughter, one for each of the four victims at her son's school.

"It was very difficult," an unnamed juror said after the verdict was announced, per NBC News. "Lives hung in the balance, and we took that very seriously. The thing that really hammered it home was that she was the last adult with the gun."

Jennifer, who faces up to 15 years per count, had pleaded not guilty to the four charges. She's set to sentenced April 9.

E! News has reached out to Jennifer's legal team for comment but has not heard back.

Ethan, now 17, pleaded guilty as an adult to charges that included terrorism causing death and first-degree premeditated murder and was sentenced to life in prison without parole in December. 

Much of the case hinged on the actions and decisions made by Crumbley and her husband James Crumbley—who has also plead not guilty to the four charges and awaits trial next month—leading up to the attack on Oxford High School.

On the day of the Nov. 30 shooting, the Crumbleys were asked to attend a meeting at Ethan's school regarding a concerning image he had drawn on an assignment which, per NBC Chicago, depicted a gun, bullet, wounded man and the words, "The thoughts won't stop. Help me."

The Crumbleys did not take their son home nor did they disclose to the school that James had gifted Ethan a 9 mm Sig Sauer handgun, according to NBC News. That same day that the then-15-year-old opened fire using the same gun, which had been in his backpack, and killed students Madisyn Baldwin, 17, Tate Myre, 16, Hana St. Juliana, 14, and Justin Shilling, 17, in addition to wounding seven others. 

When taking the stand during her trial, Jennifer told the jury, per NBC News, that while she felt regret over her son's actions, she "wouldn't have" done anything differently. She also reportedly said, "I don't think I'm a failure as a parent."

Craig Shilling—whose son Justin was one of the four teens killed in the shooting—who was present in court when the verdict was read and later spoke outside the courtroom.

"We have been asking for accountability across the board, and this is one step towards that," Craig told reporters, per NBC News. "I feel that moving forward is not going to be any easier because of what we left behind, but it gives us hope for a brighter future."

And when it comes to parental responsibility, he added, "Do your due diligence with your child. You cannot choose to take your own interest over your child, especially when it comes to mental health."

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