CNN  — 

James Crumbley, the father of the teenager who killed four students at a Michigan high school in 2021, was found guilty of involuntary manslaughter in a trial that comes a month after the shooter’s mother was convicted of the same charges.

Crumbley was convicted of four counts of involuntary manslaughter, a charge that carries a maximum punishment of up to 15 years in prison, which would run concurrently.

Jury deliberations that concluded Thursday came more than two years after his son, Ethan Crumbley, then 15, used a SIG Sauer 9mm to kill four students and wound six students and a teacher at Oxford High School on November 30, 2021.

James Crumbley is set to be sentenced on April 9 at 9 a.m., the judge said in court. His wife, Jennifer Crumbley, will be sentenced at the same date and time.

James Crumbley was shackled and escorted out of the courtroom after the verdict was read and affirmed by each juror.

Victims’ family members were in tears as the verdict was being read.

Bill Pugliano/Getty Images
Nicole Beausoleil, the mother of Madisyn Baldwin, reacts to the jury's verdict in the trial of James Crumbley on March 14, 2024.

Parents of those killed in the school shooting, including the parents of Madisyn Baldwin, Hana St. Juliana and Justin Shilling, hugged the lead prosecutor following the verdict.

Prosecutors in closing arguments Wednesday said James Crumbley was “grossly negligent” because he bought the SIG Sauer 9mm gun for his son days before the attack, failed to properly secure it, ignored his son’s deteriorating mental health and did not take “reasonable care” to prevent foreseeable danger.

“James Crumbley is not on trial for what his son did,” Oakland County Prosecuting Attorney Karen McDonald said. “James Crumbley is on trial for what he did and what he didn’t do.”

In response, defense attorney Mariell Lehman asserted the prosecution’s case lacked evidence and was based on “assumptions and hindsight.”

“You heard no testimony and you saw no evidence that James had any knowledge that his son was a danger to anyone,” she said.

In a statement after the verdict was announced, McDonald said his failure to act led to the students’ deaths.

Robin Buckson/Detroit News/Pool/AP
James Crumbley and his attorney listen to the verdict on March 14, 2024.

“Four children are dead because of the gross negligence of the shooter’s parents. In Michigan, a parent has a legal duty and James Crumbley did not meet that duty,” she said.

The cases against the parents represent a test of the limits of who is responsible for a mass shooting. Prosecutors aiming to expand the scope of blame in mass shootings have used a novel legal strategy by arguing the parents are personally responsible for the deaths because they got their son a gun and ignored signs of his declining mental health.

Parents have previously faced liability for their child’s actions, such as with neglect or firearms charges, but Jennifer Crumbley’s guilty verdict was the first time a school shooter’s parent was held directly responsible for the killings.

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Jennifer Crumbley, the shooter's mother, was convicted of involuntary manslaughter last month.

Ethan was sentenced last year to life in prison without parole after pleading guilty to terrorism causing death, four counts of murder and 19 other related charges. He did not testify in either of his parents’ trials, as his attorneys said he would invoke his Fifth Amendment right to silence.

Victim’s dad: ‘No parents should go through the hell we’re going through’

Parents of each of the four children killed in the Oxford school shooting expressed concerns about mass shootings and the mental health of children in the United States at a news conference Thursday following the verdict.

Craig Shilling, Justin Shilling’s father, said his heart was beating out of his chest as he prepared to speak.

“I could never imagine being here and I don’t want anyone else to have to be here like this. This is a very difficult thing to go through,” Shilling said.

Steve St. Juliana, father of Hana St. Juliana, said mass shootings are the “number one killer of our kids, folks,” and added more needs to be done.

“Our children are dying on a daily basis in mass murders and we do very little about it,” he said.

Buck Myre, Tate Myre’s father, urgently called for change amid what he referred to as “a mental health crisis.”

“This is a deep issue and it’s not going to be an easy one to solve,” Myre said.

“The gun is just a tool, so we’ve got to look at other things other than the gun. We gotta see what we can do to support these kids better … we need to solve this because no parents should go through the hell we’re going through,” he added.

Both Myre and Madisyn Baldwin’s mother, Nicole Beausoleil, suggested holding the school accountable. “They are going to see these families rise up against it. They are not allowed to forget,” Beausoleil said.

Mental health and gun security were key focuses in the trial

James Crumbley’s trial began last week and has been altogether similar to his wife’s trial, featuring many of the same shooting survivors, police investigators and school employees.

However, prosecutors focused more closely on his purchase of the firearm and how he stored it, while featuring less evidence about his personal life and interests. Most notably, Jennifer Crumbley took the stand in her own defense at her trial, pushing blame onto others and expressing no regrets.

In contrast, James Crumbley declined to testify. “It is my decision to remain silent,” he said in court.

The prosecution rested its case after calling 15 witnesses over the past week. The defense called one witness, James Crumbley’s sister Karen, who testified she had spent several days with the Crumbley family in April and June 2021 and did not notice anything concerning.

How the murder weapon was secured and how the shooter gained access to it has been a key point of contention.

According to testimony, James purchased the weapon for his son on Black Friday in 2021, and he later told investigators he hid it in a case in his armoire, with the bullets hidden in a different spot under some jeans.

“I will have to find where my dad hid my 9mm before I can shoot the school,” the then-15-year-old wrote in a journal entry before the shooting.

A detective said a cable lock sold with the SIG Sauer was found still in its plastic packaging, and no other firearm locking mechanisms were found in the home. However, the defense has questioned whether a different locking mechanism may have been used to secure the firearm.

Pool/WWJ/WXYZ
The cable lock that was sold with the SIG Sauer 9 mm firearm was still in its plastic wrapping in the Crumbley home, a detective testified.

In addition, two other firearms in the home – a .22-caliber Derringer and a .22-caliber KelTec – were locked in a gun safe in the parents’ bedroom dresser, but the combination to unlock the safe was “0-0-0,” the default factory setting, the detective testified.

Prosecutors also argued James Crumbley missed clear warning signs that his son needed help.

In an April 2021 text to a friend, the shooter said he was hearing people talking to him and seeing someone in the distance.

“I actually asked my dad to take (me) to the Doctor yesterday but he just gave me some pills and told me to ‘Suck it up,’” the shooter wrote.

Lehman, the defense attorney, argued there was no evidence the shooter actually asked for help and no evidence his father declined to help. “James had no idea that his son was having a hard time,” she said.

Jeff Kowalsky/AFP/Getty Images
People gather at the memorial for the dead and wounded outside of Oxford High School in Oxford, Michigan. on December 3, 2021.

Further, on the morning of the shooting, both parents were called into school to discuss Ethan’s disturbing writings on a math worksheet, including the phrases “help me,” “blood everywhere” and “my life is useless” and drawings of a gun and bullet.

Oxford High School counselor Shawn Hopkins testified he recommended the parents take Ethan out of school to get mental health treatment the day of the shooting, but Jennifer Crumbley said they wouldn’t be able to do so because they had work. James Crumbley did not protest, the counselor testified.

The school employees and the parents agreed to keep Ethan in class for the day, the employees testified. About two hours later, the teenager took the gun out of his backpack and opened fire, killing Madisyn Baldwin, 17; Tate Myre, 16; Hana St. Juliana, 14; and Justin Shilling, 17.

Obtained by CNN
Clockwise from top left, Hana St. Juliana, Justin Shilling, Madisyn Baldwin and Tate Myre were killed in the shooting in November 2021.

Prosecutors said the shooting could have been prevented if James or Jennifer Crumbley had listened to the counselor’s recommendation and taken their son out of school, or if they had mentioned to the employees they had just purchased him a gun.

“James Crumbley was presented with the easiest, most glaring opportunities to prevent the deaths of these four students, and he did nothing,” McDonald said. “He did nothing – over and over and over again.”

Lehman disagreed, saying James did not know his son had gained access to the weapon and did not believe there was an imminent, immediate threat of danger.

“James Crumbley had no idea what his son was capable of, he had no idea what his son was planning, and he had absolutely no idea that his son had access to those firearms,” Lehman said.

CNN’s Dalia Faheid and Ashley R. Williams contributed to this report.