Experts weigh in on video showing officer shooting man with knife

ST. LOUIS, Mo. (First Alert 4) - First Alert 4 Investigates uncovered exclusive video Tuesday of the moments law enforcement officers shot and killed a man on I-44 in Sullivan last year.

After Garrett Ryan was killed, his mother and her attorney question whether police should have used a different tactic instead of shooting him. But the Franklin County Sheriff’s Office and other law enforcement experts defend the officers, saying they had no choice.

To better understand what guides officers in these situations, we asked experts about officer reaction times.

“The closer someone is, the worse case it’s going to be in of reacting,” said Michael Kantor, a professor of physiology at Ohio Northern University. He has studied the time it can take for a knife-wielding subject to reach someone.

Previous guidance, he said, was the 21-foot rule — a philosophy that if someone with a knife were to charge an officer, they could cover 21 feet in just the time it takes an officer to react and fire their weapon.

That guidance used to inform police training, meaning that if a subject got closer than 21 feet, that person could injure an officer before the officer had time to defend themselves.

But Kantor said new research proves there are many more variables that challenge that rule.

“Environment, the skill of the officer, the weapons being used, the actual profile of the individual — a lot of what I’ve done is looking at males and females, young and old, fit and not fit — and how that actually impacts someone, say, running at you from a distance,” he said.

Now, departments tend to say there is no way to put an exact number on the distance at which it is appropriate to shoot.

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