(CBS4) – In the trial of Devon Erickson which came to a close this week, the notion again arose that there were opportunities to stop a school shooting before it happened. It’s not uncommon. In fact a close look at school shootings shows there are often signs that violence could happen.

“We have reviewed almost all the school shootings that have occurred since Columbine,” said Bill Woodward, Director of Training at The Center for the Study and Prevention of Violence at CU Boulder. “What we find is that there are warning signs.”

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The 2019 shooting at STEM School Highlands Ranch may have been no exception, although “We’re not really going to know what happened until someone does a similar study to what we did at Arapahoe High School. And finds out what was really going on in the background, who knew what when. Then we may know better how to prevent that kind of a problem in the future.”

The study done following the 2013 shooting at Arapahoe High detailed multiple opportunities to prevent the violence.

“For example that killer had been assessed as ‘low risk’ and when in fact when we looked through all the warning signs and everything that had happened ahead of time it was pretty clear that that person was not low risk,” said Woodward. “There were failures to find out information that would have raised his risk level.”

Arapahoe High was a lauded school, as is the STEM School and many others where shootings have occurred. People were afraid to share information there and it turns out that that was critical for no one really knowing what was happening in the school around the killer.”

A troubled student killed Claire Davis and took his own life after being confronted by a sheriff’s deputy working as a school resource officer at the school. The killer had previously threatened to kill a teacher.

Many times, the schools believe they are not likely candidates for school shootings.

“In Parkland people were actually saying, this is the perfect school. These things don’t happen here. This is a high performing school,” said Woodward.

Dissecting what happened does not merely involve a law enforcement or school review, but asking students.

“I don’t think you find out anything until you get to hearing some depositions,” Woodward imparted.

Many times schools are unaware. In talking with students a survey at a school in Colorado Springs, “We found from surveys that 5% of the kids had seen guns on the bus. Going or coming to school.”

The school took new measures to prevent it.

Safe2Tell has helped in Colorado, but Woodward says they found it was pushed more in elementary and middle schools and not as effectively at high school level. Repeated messages are like training.

“The training gets you to the point where you think you can tell on someone else, because you remember as well as I do you never ratted on your friends.”

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The mindset of the shooters of course, varies. About 40% of the time the shooter is a traumatized young person.

“And the traumatized kid is living in an environment where the parents make the big difference.”

There is a scale created by The Centers for Disease Control and Prevention called the Adverse Events Scorecard.

“If you’re abused physically emotionally sexually or neglected physically or emotionally, those are each one point … in terms of the household, if there’s mental illness in the household or an incarcerated relative, usually a parent or the mother is treated violently, the kids see the mom  beaten up, or there’s substance abuse or there’s divorce Those add up to a total of 10 possible points on the adverse childhood events scorecard.”

High scores have been shown to predict cardiac issues later in life.

Many other school shooters have some degree of psychosis.

“The ones that are psychotic and are hearing voices telling them to kill someone, often the parents are just not in that loop … Or you look at the psychotic kid as in the case at Columbine. And (Eric) Harris was believed to be psychotic, and in that case as well that, we don’t really see that coming from the parents.”

Parenting can certainly have a role, but Woodward notes it’s no necessarily one type of parenting or another.

“It’s usually that the parents aren’t consistent. In other words the kids can’t depend on a strict parent to be strict or a liberal sort of we-don’t-care-what-you-do kind of parent to be permissive, jumping back and forth between those is actually more dangerous than being consistent.”

The Center has helped develop a program called “Safe Communities, Safe Schools.”

A total of 44 schools have taken part. None have had shootings, although Woodward notes that doesn’t necessarily prove anything. But for 8 years, they have used a federal grant program to go into those schools and survey all students.

“It’s just critical to know today what exactly kids are thinking about, whether some kids think violence is OK?”

They also look at whether there is much drug and alcohol abuse, bullying and look for mental health issues. Six months ago the program ran out of money. The Center has asked The State of Colorado to step in with help, but that has yet to happen.

It costs about $25,000 a school to do the work. Woodward hopes The STEM School will get a close look, too, to see what can be learned.

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“I think it’s important that that happen that someone somewhere gets a better handle on that’s occurred and how it could have been prevented because I don’t think we have a handle on that right now.”

Alan Gionet