I work for police control and we have ASBO's for persistent violent callers as well, but they are always with the proviso, "however treat each call on it's own merits, a crime may have been committed" meaning if you fail to put and incident in and send the police and as Tom says, the person has suffered a crime/injury - your job is on the line. Therefore you create an incident & you always send the police. It’s a farce. It’s basically a cover your arse exercise for the management, if an officer gets injured and complains, they can say – "we did protect you we got an ASBO".