There is the concept of the Castle Doctrine, where you are allowed to use deadly force (within reason) to defend yourself and your family when someone attempts to assault you within your own home. Not all states have it but regardless, it is null and void when it comes to the police.

EDIT: I'm not sure why this is being downvoted? We're discussing gun ownership in America, when it is legally allowable to use said firearms and the fact that none of that matters when it comes to Police entering your home, all in the context of police acting like the Gestapo at this woman's home.