Parkland school shooting is being reenacted by ballistics experts. Here’s why.

May 20, 2023

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Reliving America’s deadliest high school shooting is all about whether “good guys with guns” can really stop mass killings.

America’s deadliest high school shooting in history will be reenacted Friday at Marjory Stoneman Douglas High School in Parkland, Florida, as part of a lawsuit against a former sheriff’s deputy who failed to intervene while 17 people were gunned down inside.

At least 140 live rounds of bullets will be fired inside with the aim of determining whether the former deputy, Scot Peterson, has a viable defense in claiming that he stayed outside the building because he couldn’t determine where the gunshots were coming from. He was found not guilty in June of criminal charges of felony child neglect, culpable negligence, and perjury. But he could still face liability in the civil suit brought by victims’ families and a survivor.

Their lawyers have indicated that they intend to use the same type of semi-automatic rifle and caliber of cartridges used by the shooter and would also sound the fire alarm as part of the reenactment. No students will be on campus Friday while it’s underway.

Whether or not Peterson’s defense has merit, his failure to neutralize the shooter raises a familiar sticking point in the gun control debate: whether a “good guy with a gun” can actually put a stop to gun violence. It’s a theory long promoted by the National Rifle Association and some Republican lawmakers in place of stricter gun control measures. “We know from past experience that the most effective tool for keeping kids safe is armed law enforcement on the campus,” Texas Republican Sen. Ted Cruz said in May 2022.

But that theory didn’t prove true in Uvalde, Texas, where it took 77 minutes for officers to kill the gunman who fatally shot 19 students and two teachers at Robb Elementary School last year despite the presence of 376 officers from various law enforcement jurisdictions. Some of them reportedly delayed going inside the school because they feared the gunman’s AR-15-style rifle. An armed school resource officer was stationed at the school but was not on-site at the time of the attack.

Nor was a former police officer who worked as an armed security guard able to prevent last year’s shooting at a supermarket in Buffalo, New York. He and nine shoppers were killed in the attack, which the shooter carried out with a Bushmaster semiautomatic rifle that he illegally modified to increase its capacity.

Police are trained to immediately confront shooters, even if they’re alone at the scene. But in mass shootings, they more often than not fail to neutralize shooters before they have already managed to inflict injuries and deaths. And bystanders are even less successful in doing so.

According to a database maintained by Advanced Law Enforcement Rapid Response Training Center at Texas State University, there were 520 active attacks — defined as when one or more people are “actively killing or attempting to kill multiple unrelated people in a public space,” including but not limited to shootings — between 2000 and 2022. In most of those cases, police were unable to stop the attacker, either because the attack had already ended by the time they arrived or because the attacker either surrendered or committed suicide.

Only in 160 cases were police able to successfully intervene by shooting or otherwise subduing the attacker.

A 2021 study from Hamline University and Metropolitan State University also found that the rate of deaths in 133 mass school shootings between 1980 and 2019 was 2.83 times greater in cases where there was an armed guard present. The researchers argue the results suggest the presence of an armed guard increased shooters’ aggression and that because many school shooters have been found to be suicidal, “an armed officer may be an incentive rather than a deterrent.”

Nevertheless, at least 28 states permit school staff and teachers to carry guns on campus. In the wake of the Uvalde shooting, Texas has required every school to have an armed officer on campus.

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