Doc on school shooter's parents reveals how prosecutors built case

On Nov. 30, 2021, a 15-year-old boy killed four students and injured seven others in a shooting spree at Oxford High School in Michigan. He pleaded guilty to all 24 charges against him and was sentenced to life in prison.

Just three days after the shooting, Oakland County prosecutor Karen McDonald made the historic decision to charge the shooter's parents, Jennifer and James Crumbley, with involuntary manslaughter. The Crumbleys are the first parents ever to be charged, then convicted, in the United States for a mass shooting committed by their child.

In a new hourlong documentary premiering April 18 on Hulu, "Sins of the Parents: The Crumbley Trials," ABC News Studios offers exclusive behind-the-scenes access as the prosecution builds their case over a two-year period.

"I know we have a legal duty as parents to protect other people from dangerous kids," McDonald says in the documentary.

"This is about parents who largely ignored their son, neglected…his cries for help. And then bought him a gun," said chief assistant prosecutor David Williams.

The shooter's journal entries revealed that he blamed his parents for his mental decline, stating that they didn't listen or get him a therapist. During the trials, evidence showed how the Crumbleys were engaged with their son's interest in guns.

While investigating Ethan's parents, McDonald and her team uncovered a text message sent by Jennifer Crumbley to her son. The text read, "LOL, I'm not mad. You have to learn how not to get caught." Jennifer Crumbley did not appear to be angry with him after learning that he had been researching bullets in class.

Testifying in her own defense, Jennifer Crumbley said, "You know, as a parent, you spend your whole life trying to protect your child from other dangers. You never would think you have to protect your child from harming somebody else."

James Crumbley's defense attorney, Mariell Lehman, warned that the prosecution's argument could set a dangerous precedent, blurring the line between parent and criminal.

"I think that if somebody is made out to be a bad parent, then…their behavior can be contorted into criminal behavior," Lehman says. "I think that James Crumbley was…made out to be someone that he's not."

A jailhouse phone call with James Crumbley is one of several which the prosecution has said were threatening against the Oakland County prosecutor.

"When I get out of here, I am f------ on a rampage, Karen. Yes, Karen McDonald, your a-- is going down and you better be f------ scared."

Crumbley's defense attorney characterized those remarks as venting, noting that some statements were from years before the trial began.

The Crumbleys were convicted of involuntary manslaughter and sentenced to 10-15 years in prison.

After the trial, Judge Cheryl Matthews said the Crumbleys showed a lack of concern toward guns and glorified their possession and use.

The story about parents who ignored their son's cries for help and bought him a gun started on Nov. 26, 2021, at an Oxford gun store. James Crumbley purchased a Sig Sauer 9-mm. handgun with his son.

Entries from the child's journal revealed he had been wanting his parents to buy him a gun. That same day, he posted on Instagram that he had received his "new beauty today," Chief Assistant Prosecutor David Williams said.

The next day, he went to the gun range with his mother, and surveillance footage captured him showing her how to use the firearm. Two days later, a teacher caught him researching ammunition and left a voicemail for Jennifer Crumbley expressing concerns.

"I'm calling from Oxford High School," the voicemail said. "One of the teachers had sent an email to the office because she was concerned. He was on his phone looking at bullets."

Jennifer Crumbley was initially concerned when she texted her son about the disturbing voicemail she had just listened to, evidence presented by the prosecution showed. After he downplayed the situation, she reassured him she wasn't angry and advised him to be more careful.

On Nov. 30, 2021, he turned in math homework that included drawings. The school's counselor texted what they felt were disturbing drawings to Jennifer Crumbley and called her to come into the school. She responded, saying she couldn't come in.

After the conversation, Jennifer Crumbley texted her husband James about the situation. She told him she was concerned, and James Crumbley responded that he was very concerned after seeing his son's drawings.

"Eventually, they both came in," Marc Keast, Oakland County Assistant Prosecuting Attorney, said. "The school counselor told them, I think you need to get him services. You need to take him home. And both Jennifer Crumbley and James Crumbley said they couldn't do it. They're being told by a school counselor that this is suicidal ideation."

Jennifer Crumbley's lawyer, Shannon Smith, challenged this after Jennifer Crumbley told her on the stand that the school counselor told he didn’t believe her son was harmful.

“He told us that he didn't feel my son was a risk and actually gave him the option if he wanted to stay at school or go home,” Jennifer Crumbley said. “My son wanted to stay at school. And then I said, I'm going to go back to work.”

Prosecutors said during the trial that neither Jennifer nor James Crumbley mentioned to the counselor that they bought him a gun four days earlier, and they did nothing to look for it. Approximately 90 minutes later, their son shot and killed Hana St. Juliana, 14, Tate Myre, 16, and Madisyn Baldwin and Justin Shilling, both 17, and injured seven others.

After the shooter's actions gained widespread attention, McDonald's investigation shifted from him to his parents once it was discovered where he obtained the gun.

"As soon as I heard that they were called to the school that day," McDonald said, "the messages about " ‘LOL don't get caught.’" Those were very, very concerning to me. And so, when they presented the case on the shooter, I addressed that: 'What about the parents?'"

During a press conference, McDonald stated, "It is egregious that a parent could read those words and know that their son had access to a deadly weapon that they gave him. It is unconscionable, and I think it is criminal."

"When you get down to the actual elements, their big defense has been that they locked their weapon," McDonald said. "First, they went to the substation and were asked at least two or three times where the weapon was, and they never said it was locked."

James Crumbley told the police that he had hidden an unloaded gun in his bedroom armoire. Based off evidence that was presented to the jury, Jennifer Crumbley was the last adult to have possession of the gun, and the video of her walking out of the shooting range with the gun is the last known evidence of its whereabouts prior to the shooting. The jury found her guilty based on this key factor, as stated by the jury's forewoman to the media.

Jennifer Crumbley was found guilty on Feb. 6, 2024, on all four counts of involuntary manslaughter. As soon as Jennifer Crumbley's trial ended, James Crumbley's trial started.

His defense was different from Jennifer Crumbley's due to him making the 911 call that his gun was missing and having no knowledge of his obtained access to a gun he had hidden.

"It boils down to reasonable foreseeability and whether or not James had knowledge of what his son was capable of or what his son was planning," defense attorney Mariell Lehman said. "He had no knowledge that his son had obtained access to the firearms that James thought he had responsibly hidden and prevented his son from having access to."

McDonald and her team focused on how James Crumbley was not shocked that his son obtained the gun.

"When you think about what he knew about the gun, about his son, and then he sees that drawing, what do you do?” Williams asked. "And any responsible person is going to do a couple of things. They're going to ask him what's going on, and they would look at that drawing and say, my God, that's the same gun we just bought him."

A month later, James Crumbley was also found guilty on all four counts of involuntary manslaughter.

"No amount of years in prison is going to make their grief or pain any less," McDonald said. "It's not going to bring anybody back."