Someone ...

... doesn't know what he's talking about:

“If someone pulls a knife on you, it’s okay to come back at them with a gun,” Carroll said, “But if they’re 18 feet away from you with that knife and you shoot them, you might be in trouble. Were you really in imminent danger?

And Mr Carroll is a former detective with the Chicago Police Department. Sheesh ...

Ever heard of the Tueller Drill? That's the one developed by Dennis Tueller, who wondered just how quickly a cutting edge weapon-armed attacker could cover 21 feet. He published his findings in SWAT magazine in the 1980's, and Massad Ayoob expounded on the idea.

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