I think maybe the tide turned against Jennifer Crumbley on the witness stand, when she insisted there had been no sign that her son was mentally ill.

The notion that mass murderers and serial killers can seem just like everyone else is a shopworn cliché, and doesn’t stand up, in most cases, to the barest scrutiny; dig just a little, and plentiful evidence emerges that warning signs, lots of them, went unnoticed or ignored.

Crumbley’s son is the Oxford High School shooter, who killed students Madisyn Baldwin, 17, Tate Myre, 16, Hana St. Juliana, 14, and Justin Shilling, 17, injuring six more and a teacher, in a deadly Nov. 30, 2021 rampage. A pre-trial psychiatric assessment revealed that the shooter had had suicidal thoughts and a history of bizarre behavior; had sent text messages to his parents about demons and hallucination; made drawings of bloody bodies with ominous messages shown to his parents by school administrators. And yet the Crumbleys, by their own admission, purchased the firearm used in the shooting as a gift for their son, and took him to the gun range to practice.

What else did Crumbley see and choose to ignore?

Legal experts told Free Press courts reporter Tresa Baldas in 2022 that Oakland County Prosecutor Karen McDonald and her team had a steep standard to meet in this nearly unprecedented prosecution: Convincing a jury not that the Crumbleys – James Crumbley, the Oxford shooter’s father, is awaiting trial – could have prevented the shooting, but foreseen it.

And so I wonder if that was the moment that swayed the jury. If Jennifer Crumbley’s patently absurd contention that her son was a normal kid, barring a little anxiety and the occasional joke about demons, made the jury question her veracity: What else did Crumbley see, and choose to ignore?

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Because on Tuesday, a jury found Crumbley guilty on four counts of involuntary manslaughter. Last year, the shooter – 15 at the time of the killings – was sentenced to life in prison without parole, a rare prison term for a person of his age that reflected the horror of the crime.

Jennifer Crumbley will certainly appeal this verdict.

But this is a resonant moment.

For decades, lawmakers have failed to act on gun safety

Michigan, on Nov. 30, 2021, had no law requiring the Crumbleys to keep firearms out of their son’s hands, no matter the warning signs. That’s why this prosecution was an uphill climb.

And, I am sad to report, that didn’t change on Nov. 31, 2021. Or in the days and months after, not until another mass shooting happened, almost one year ago at Michigan State University, perpetrated by a killer who, like Crumbley, displayed plenty of warning signs – and a change in the state Legislature placed Democrats responsive to Michiganders in control.

Last year, the Legislature passed laws requiring universal background checks, secure storage of firearms and allowing judges to remove firearms from the possession of dangerous people. They’ll soon, finally, become law. A vast majority of Michiganders support such laws, but for decades, lawmakers have failed to act.

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For all the attention we pay school shootings, it is not lost on me that that the greatest risk of gunshot my 13-year-old son faces comes not at school, but at the home of a friend who does not understand that their parents’ poorly secured firearms can be deadly.

“The hope has to be you see this ruling, and you see the new law, and it makes every adult think twice,” said state Sen. Mallory McMorrow, D-Royal Oak, who co-sponsored the laws. “This was really malicious, but most of the time, it’s an accident.”

Gun owners who oppose gun reform laws often draw a line: They’re up to the task of responsible gun ownership. Other people are the problem.

By the numbers, some of them are wrong.

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Two years ago, guns became the leading cause of death of American children, a singular distinction among peer nations. Some 34% of gun deaths among children under 5 are accidental, a study by the magazine Injury Epidemiology found; 64% of all accidental child shootings happen at home, with a weapon owned by a family member. Small children are more likely to shoot themselves. Boys 10-14 are more likely to shoot a friend. The vast majority of shooters and victims are male. And in 92% of accidental child shootings, the firearm was loaded and unsecured.

The two previous Michigan prosecutions of family members for unsafe gun storage involved accidental deaths.

“The safe storage laws that will be on the books, in a number of days, are going to make it clear to every parent that they need to store their guns safely,” McMorrow said. “If people can be tried and held accountable if your kid gets ahold of a gun, it will change behavior.”

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It’s hard to look at the past, even a horrific tragedy like Oxford, and say that this action or this decision could have stopped it. But surely we could have passed these laws decades ago. Surely some slain children could have been saved.

Here’s what it comes down to: A biometric gun safe is $63 on Amazon.

No more excuses.

Nancy Kaffer is editorial page editor of the Detroit Free Press, where this column first published. Reach her at nkaffer@freepress.com.

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This article originally appeared on Detroit Free Press: Jennifer Crumbley ignored signs. Jury found her guilty because of it