Steven Harris has been a lawyer since 1979, and he often defends federal agents and police officers in use of force cases. He is also a highly trained shooter, having trained with us and several other schools. Here is an article he wrote for Modern Service Weapons, but first some comments from me.
Claude Werner (The Tactical Professor) frequently writes about negative outcomes arising from a homeowner going outside to challenge a suspected intruder. If you think there is a deadly threat outside, why go outside? Here, Harris details some legal issues involved. See
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