David Walcher had just gotten back from a celebratory breakfast and was on his way to lunch with a fellow member of the Jefferson County Sheriff’s Office.

“Every year, the county leaders would have the ‘Good News Breakfast,’” said Walcher, at the time a lieutenant. “That was actually held that morning at the Jeffco Fairgrounds. It was business, schools, government — a big breakfast just to celebrate the good things happening in Jeffco.”

Just hours later, he’d walk out of his office, get in his car to pick up his colleague and hear a barrage of radio traffic of “what was just starting to be Columbine.”

“And I remember thinking to myself, I don’t know what’s going on yet, or where,” said Walcher, whose car was cut off by an investigator’s vehicle going by at high speed. “It just took seconds, when I realized what was happening.”

From the different calls coming in to law enforcement, deputies thought four to six shooters may have thrown Columbine High School into chaos the morning of April 20, 1999, said Walcher, who was designated the incident commander for the scene by the sheriff and undersheriff.

“I just tried to do everything I could to figure out what was going on,” Walcher said. “It was difficult — you don’t train (for that). These days, we’re incredibly better, and — not used to it, but we know these things happen.”

Some thought the first deputies on the scene could have handled it differently, but Walcher said the response is difficult to evaluate.

“The reality is, no one had ever had to deal with something like that. We dealt with it to the best of our ability at that time,” Walcher said.

“I’ve been in law enforcement for 38 years,” Walcher said. “There’s really not a day that goes by that I don’t think about it in some capacity, 20 years later.”

More than a decade after Columbine, Walcher would face — as the Arapahoe County undersheriff — the 2012 Aurora theater attack and Arapahoe High School shooting in 2013. He’d go on to serve as Arapahoe County sheriff until early this year, following an election defeat.

After years of responding to and reading about school shootings, Walcher sees progress in how officers approach potential tragedies.

“Never have I seen law enforcement take even minor threats more seriously than they do in today’s world,” said Walcher, a member of the National Sheriffs’ Association’s subcommittee for preventing school violence.

Schools across the country have likely implemented certain security measures, but Walcher said they shouldn’t become “prisons.”

“Maybe it’s schools, maybe it’s law enforcement, maybe it’s mental health, maybe it’s parents, maybe it’s the entertainment industry” that all need to be part of a solution, Walcher added.

Friends, family, teachers and others who come into contact often with students should watch for “red flags” in a student’s life, Walcher said.

“When you see a kid start to change their behavior, be less social, grades plummet, or they’re in sports and then they stop, or when mom and dad get divorced, maybe they become loners,” Walcher said, adding that bullying should be watched for, too. “Some of those tipping points that drive them away from everyone … that’s where the prevention is so critical.”

He hopes people understand that incidents like Columbine can happen in their communities. The problem isn’t going away, he said, but incidents can be averted.

“Could we have a more positive effect on this?” Walcher said. “Absolutely, absolutely.”