A few years ago there was a South Australia idiot threatening all sorts, including rape and murder, on a forum, I got in email contact with a detective from South Australia Police's Electronic Crimes and one day, whilst this idiot was being brave from behind his keyboard, the Police came knocking at his door
This guy lives in San Francisco, I've already successfully goggled SF's Police email addresses, any more nonsense from him and I'll be emailing his local cops.