Mother of Oxford school-shooting suspect was having an affair and snuck away from work to meet with her partner at a Costco parking lot, coworker says

• Jennifer and James Crumbley face involuntary-manslaughter charges in connection to a school shooting.
• Jennifer Crumbley's coworker testified Crumbley and her husband were "seeing other people" in 2021.

At a court hearing on Tuesday, a coworker of Jennifer Crumbley said Crumbley was seeing someone outside her marriage throughout last year and would sneak away from work to be with her extramarital partner.

Jennifer and James Crumbley both face involuntary-manslaughter charges in connection with the Oxford High School shooting in November that left four students dead. The Crumbleys are accused of making a firearm too easily accessible to their son, who is accused to carrying out the attack, and ignoring warning signs that he was depressed.

Both parents face up to 60 years in prison and $30,000 in fines if convicted.

At a preliminary hearing on Tuesday for the couple's manslaughter trial, one of Jennifer Crumbley's coworkers testified that both parents were "seeing other people" throughout 2021.

Amanda Holland said in Michigan's 52nd District Court that Crumbley was in an extramarital relationship throughout 2021 but couldn't remember specifically when the affair took place. She said Crumbley would often sneak away from work to go see a person in the parking lot of a Costco.

Holland said in court that the Crumbleys separated at some point during 2021 but continued living in the same house. Holland testified that the Crumbleys resolved their marital issues around their anniversary but again could not remember the specific date.

A defense attorney for Jennifer Crumbley objected to prosecutors asking questions about the couple's extramarital affairs, saying those were irrelevant. The prosecution said the information was relevant because the Crumbleys had a "duty" to protect their community from their son and "what they exposed their son to" should be relevant.

Judge Julie Nicholson overruled the objection, though she said, "Whether or not there was some type of extramarital relationship between the parties and a duty to the community, I don't know that that is intertwined."

Holland testified that Crumbley returned to work on November 30 from her son's school and told her that the school was requiring her to put her son in counseling. According to Holland, Crumbley showed her a math worksheet that her son completed earlier in the day on which he wrote that his life felt useless and, "The thoughts won't stop. Help me."

Holland testified that she found the worksheet "disturbing."

Crumbley told Holland that she felt like a "failure as a parent" after her meeting with the school, but Holland said her tone seemed "sarcastic." Holland testified that she recommended that Crumbley go pick her son up from school to "spend some time with him."

Holland said Crumbley told her that she was planning to take her son to a horse barn after school where her family kept their horses. Kira Pennock, who works at the horse barn, previously testified that Crumbley was planning to bring her son by on November 30 for riding lessons.

On cross-examination, Holland told the defense attorneys that she didn't know much about the Crumbleys' son or that he was involved in extracurricular activities and was working on becoming a soccer referee.

Shannon Smith, a defense attorney for Jennifer Crumbley, also asked Holland whether she was aware that the school told Crumbley that her son was "not a threat to anyone" on November 30. Holland replied, "No."