As the mother of a school shooter, Jennifer Crumbley’s reputation has stains that can never wash clean. Ms. Crumbley is now spending her days hunched in a Michigan courtroom, weeping at times as she listens to the testimony against her. The jurors may condemn her to prison, or they may absolve her, but she will always be a walking symbol of gun violence and bad parenting.

On Nov. 30, 2021, Crumbley’s 15-year-old son, Ethan Crumbley, drew a 9-millimeter semiautomatic handgun from his backpack and opened fire, killing four students and wounding seven people at Oxford High School. His parents had bought him the gun as an early Christmas present; his mother celebrated by taking Ethan to a shooting range, an outing she called a “mom and son day.”

Both parents face charges of involuntary manslaughter; James Crumbley, Ethan’s father, will be tried later. Prosecutors argue that their indifference to their son’s collapsing mental health, even as they gave him access to the murder weapon, make them criminally responsible for his attack. It’s a remarkable and unprecedented gambit.

Hundreds of mass shootings have struck American schools in recent decades, leading to prosecutions of the shooter and civil lawsuits against schools, administrators or parents. The Crumbleys are the first parents to face homicide charges for a school shooting by their child.

I’ve listened to hours of testimony, in the trial and in pretrial hearings, on the dynamics of the Crumbley family and the events leading up to the shooting at Oxford High School. The more I’ve heard, the less clearly I’ve understood the case against the parents. Ms. Crumbley doesn’t strike me as an insightful or affectionate mom — or even, perhaps, a very nice person. But she’s more complex than the monstrously callous and neglectful figure suggested by her dour mug shot and the few choice details about her personal life that have floated into the headlines. The case against the Crumbleys is more complicated than it sounds.

The prosecution of the parents seems to be motivated, at least partly, by the grief of a local community, and the ambient desperation of a country trapped in the recurring nightmare of mass shootings.