It's a good clause, it gets abused.
I walk by your house on some other errand, I hear screaming, I look in the window and see you bound and gagged. I hear the screaming from another part of the house.
A. I call it in and wait for a warrant.
B. I kick in a door and end the situation.
c. you are swingers into that kind of thing and it still goes sideways.
I think you ment that you "claim" you heard a scream so you break down the door, the person in the chair had a ball gag in (so you didnt hear them) and the other person was downstairs eating a sandwich so they didnt either.... but once your in, you are in like flint. So you had to shoot the guy makeing a sandwich, he was holding a knife (butter knife) and didnt drop it as soon as he saw someone with a gun in his house, you screamed something but it took him longer then your reaction time to realise that you claimed to be a cop and told him to drop it. 31 rounds later (he was hit by 3 of them) IA shows up for an internal investigation and find that it was a justifiable shooting and his wife (upstairs in the ball gag) is charged with resisting arrest....
(Sorry I used 'you' in this context, but its easier then typeing out 'the responding officer' each time)