A Michigan jury issued a historic verdict on Tuesday, finding Jennifer Crumbley -- the mother of Michigan school shooter Ethan Crumbley -- guilty of four counts of involuntary manslaughter for her role in the 2021 shooting.
The case was a rare example of a parent facing criminal charges for failing to address warning signs about their child and preventing them from accessing the weapon used in the shooting. The shooter's father, James Crumbley, will have a separate trial in March, where he faces the same charges.
Prosecutors argued that the Crumbley parents, who bought their son the weapon used in the shooting as a gift, failed to prevent the attack despite school officials warning them the morning of the shooting that he was showing concerning signs. The school asked the Crumbleys to take their son for mental health care that day, but the parents said they had to go back to work and would arrange care for him.
Ethan, who was 15 at the time of the shooting, killed four of his classmates and injured seven others when he opened fire at Oxford High School in November 2021.
Experts told ABC News the case has set a precedent for gun owners and outlines responsibilities for parents of individuals showing warning signs. Everytown for Gun Safety -- a group that advocates for gun control -- applauded the guilty verdict and said it sets an important precedent.
"Today's verdict underscores the important responsibility of parents and gun owners in preventing children from having unsupervised access to deadly weapons," Nick Suplina, senior vice president for law and policy at Everytown, said in a statement.
"Plain and simple, the deadly shooting at Oxford High School in 2021 should have -- and could have -- been prevented had the Crumbley's not acquired a gun for their 15-year-old son," he continued. "This decision is an important step forward in ensuring accountability and, hopefully, preventing future tragedies."
Legal experts argued this verdict could open the door for more prosecutors around the country to hold parents responsible in shootings.
"Every law student learns in the first year that the acts of a responsible person cannot (usually) make another person responsible. Even when others do terrible things, no one else is responsible unless they are an accomplice. But the facts are so damning -- the parents did not tell the school that they had bought him a gun and he might be armed -- that it almost felt like the case was meant to push that legal principle to its limit," Ekow Yankah, a lawyer and the associate dean for faculty and research and professor of law at the University of Michigan, said in a statement.
"The prosecutor achieved a conviction here. Other prosecutors will view it as both precedent for the next high profile example and a tool to force others similarly situated to plea to a sentence," Yankah said.
Other attorneys argued that the jury may have set a threshold for negligence.
"When we look at this verdict, what I see is the jury and the morals of that particular community say that these actions by these parents rose to the level they were found criminally negligent of involuntary manslaughter," Channa Lloyd, attorney and ABC News legal contributor, told ABC News Live.
"This jury is essentially sending a message that says that you cannot -- the signs that were there, the red flags that were given -- knowing that information, still hand this young man a gun without any sort of proper controls and say you were acting as a responsible parent," Lloyd said.
Another attorney said this ruling means parents need to be diligent about knowing what is going on with their children.
"It definitely sets what we call in the legal community a 'bright line rule.' And so I would say you take what the elements of the Jennifer Crumbley case is and see if it applies to others," Brian Buckmire, an attorney and ABC News contributor, told ABC News Live on Tuesday. "In Jennifer Crumbley's case, it was a matter of red flags, the school bringing them in, seeing the drawings on the math homework, the text messages and the fact that -- I think that this is an important part -- she supplied the gun through her husband and she was the last one to see him operate that weapon.
He continued, "And there's a big question mark as to whether or not the father properly secured it; clearly not enough with that just '0-0-0' password and knowing that he ultimately did commit a mass shooting. All parents, we're all on notice now: Make sure you know what's going on with your children and make sure they don't have access to deadly weapons if there are issues."
Brady United, a gun control advocacy group, said in a statement that holding Crumbley criminally responsible sets an important precedent for gun safety.
"Irresponsible behavior like Jennifer Crumbley exhibited is why 76% of school shooters under the age of 18 get their firearms from home. The consequences are irreparable, and the families of the children killed in this brutal attack will never again get to hold their children close and watch them grow," Kris Brown, the president of Brady, said.
"This verdict will not bring back the children killed or heal the wounds of those injured, but it does bring a shed of justice for the families who were so egregiously wronged. Today's decision sends a powerful message to parents and other parties that they can be responsible for their actions that foreseeably contribute to gun violence even if they don't pull the trigger," Brown added.