Definition Of Harrassment

Q: I need a legal definition of stalking, for research and because I need to advise people. The definition I have includes a "credible threat". Does this apply under English Law. How many contacts would realistically be considered stalking, for example, letters requesting a meeting. What I am trying to find out is where would attemptimg to redress a grievance end and stalking begin, e.g. a situation where someone is constantly (three times a week approx.) being phoned for money the "stalker" feels they owe when they don't. Would contact with a person's friends to find out about them constitute stalking a person when that person was not contacted. If a journalist did this, could they be accused of stalking. I,m currently reading a research paper which I cant begin to make sense of because there is no working definition of the term

A: