How would you feel if I called the cops on him?
Why do you want to call the cops on him? Are you in danger?
Yes, I am afraid that he is going to pull a gun on me from his arsenal of firearms.
It does sound like a dangerous situation so it is good to call the police as long as it is an emergency. You don't want to get in trouble for calling for a situation that is not urgent.
I'm going to make it urgent and say that I saw him doing drugs. That is a good reason for the police to raid his place.
There are real people who might need the police services if you are making up the drugs thing. Did you know in a lot of places drugs are now legal to use recreationally?