(CNN) — It has become a tragically familiar scene in American life: law enforcement officers descending on a packed school where a gunman is on the loose. A procession of students, their hands raised, slowly making their way out of the danger zone.
But the handling of Friday’s shooting at Arapahoe High School — just 10 miles from the scene of the 1999 Columbine High School shooting where two students killed 12 classmates and a teacher before fatally shooting themselves — drew important lessons from the earlier bloodshed.
At Arapahoe High School, where a 15-year-old female student was critically injured before the shooter turned the gun on himself, law enforcement officers responded within minutes and immediately entered the school to confront the gunman rather than surrounding the building, authorities said.
As the sound of shots reverberated through the corridors, teachers immediately followed procedures put in place after Columbine, locking the doors and moving students to the rear of classrooms.
“That’s straight out of Columbine,” Kenneth Trump, president of National School Safety and Security Services, a Cleveland-based consulting firm, told CNN Saturday. “The goal is to proceed and neutralize the shooter. Columbine really revolutionized the way law enforcement responds to active shooters.”
Arapahoe County Sheriff Grayson Robinson credited the quick police response time for the fact that student Karl Pierson, the gunman, stopped firing on others and turned his weapon on himself. Just five minutes passed between the time deputies received the 911 call and the time they were standing over the shooter’s body, he said.
Robinson said the so-called active shooter response protocol, which was developed after Columbine, was put into place.
“Our active shooter protocol was immediately initiated by our school resource officer,” Robinson told CNN affiliate KCNC in Colorado. “The officer went immediately to the threat as he is trained, and all of the responding deputies and police officers also activated our regional active shooter protocol. And that is to go to the threat and try to eliminate the threat while keeping students and staff safe.”
The school resource officer first reported the shooting over his radio at 12:33 p.m. and “went immediately to the threat, as he was trained,” Robinson told CNN Colorado affiliate KMGH.
Friday’s shooting came on the eve of the one year anniversary of the Sandy Hook Elementary School massacre, where Adam Lanza killed 20 first-graders and six adults at the now-demolished elementary school in the second-deadliest school shooting in U.S. history.
“It’s very unfortunate that we have to say that there’s a textbook response on the way to respond to these, because that textbook was written based on all of the incidents that we’ve had and the lessons learned,” Trump said.
Trump said both Sandy Hook and the latest shooting in Colorado highlight the importance of “training and engaging” school support staff — from custodians to school secretaries to maintenance and food service workers — on how to best respond during these incidents. In Sandy Hook, a school custodian’s 911 calls provided authorities some of the first information about what was happening.
“Often these people are not getting training in school emergency planning,” Trump said. “In a critical incident, they may be the first person to respond.”
At Arapahoe High School, a school janitor spotted Pierson, whose intended target was a faculty member, in his tactical gear, he told CNN affiliate KMGH.
“It just looked weird,” Fabian Llerenas said. “He went in, and I heard two pops. That’s when I knew. I said, ‘They are shooting in the school.'”
Llerenas said he called 911 and then escorted the targeted faculty member out of the school.
Pierson had fired at the man but missed, Llerenas told KUSA.
“He was so [shaken] up, he felt the wind hit, out of the shotgun just blew his hair, but it didn’t hit him. It was that scary for him,” Llerenas said.
“In my opinion, that was the most important tactical decision that could have been made,” Robinson said. The faculty member “left that school in an effort to try to encourage the shooter to also leave the school.”
Trump said other lessons learned from Columbine included the controlled evacuations and pat-down searches of students in a secure area. Self evacuations can create chaos for the police.
Additionally, schools now have predesignated parent-student “reunification centers” to prevent parents from showing up at the scene and interfering with law enforcement, as was the case in Sandy Hook, Trump said.
“The lessons of Columbine are still the best practices,” Trump said.
After Sandy Hook. Trump said, some officials advocated a “run, hide and fight” approach developed for workplace shootings in which teachers and students are encouraged to be prepared to throw things at gunmen. Some even suggested that elementary school students use items such as cans of soup to attack gunmen. Trump called it a “high risk, high liability proposition.”
“The good news is that we’re getting better at preventing and responding to these incidents,” he said. “The bad news is that there will be cases that slip through the cracks.”
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