in, and i decide that i've got a choice of either shooting or being shot. >> within seconds, nicholas brady lying dead. >> after i shot him, i sat down in this chair and. i was just tingling. adrenaline. >> but the killing isn't over because nick brady's partner in crime is right behind him. >> and somebody else starts down the stairs. >> haley keefer is about to face the same fate. >> i wasn't thinking, i was just. they're ganging up on me, so i killed her. two. >> oh my god. >> i have. >> to ask byron. >> after the shooting and it's done. >> why didn't you call law enforcement to report what happened? >> i was pretty much afraid to do anything. it seemed sort of irrational now. but just because my thanksgiving screwed up, i don't need to screw up yours. >> byron smith admits he shot the teens, but he says he was protecting his home after a rash of burglaries in the area. >> normally when i do something, i justify it. >> retired sheriff michael wetzel says minnesota's so-called castle doctrine permits residents to use deadly force if necessary, to protect themselves and their property. >>