Stalker

Stalking is unwanted or obsessive attention by an individual or group towards another person. Stalking behaviors are related to harassment and intimidation and may include following the victim in person or monitoring them. The term stalking is used, with some differing definitions, in psychiatry and psychology, and also in some legal jurisdictions as a term for a criminal offense.

According to a 2002 report by the U.S. National Center for Victims of Crime, "virtually any unwanted contact between two people that directly or indirectly communicates a threat or places the victim in fear can be considered stalking", although in practice the legal standard is usually somewhat more strict.

The difficulties associated with defining this term exactly (or defining it at all) are well documented.

Having been used since at least the 16th century to refer to a prowler or a poacher (Oxford English Dictionary), the term stalker began to be used by the media in the 20th century to describe people who pester and harass others, initially with specific reference to the harassment of celebrities by strangers who were described as being "obsessed". This use of the word appears to have been coined by the tabloid press in the United States. As time went by, the meaning of stalking changed and incorporated individuals being harassed by their former partners. Pathé and Mullen describe stalking as "a constellation of behaviours in which an individual inflicts upon another repeated unwanted intrusions and communications". Stalking can be defined as the willful and repeated following, watching and/or harassing of another person. Unlike other crimes, which usually involve one act, stalking is a series of actions that occur over a period of time.

Although stalking is illegal in most areas of the world, some of the actions that can contribute to stalking can be legal, such as gathering information, calling someone on the phone, sending gifts, emailing or instant messaging. They become illegal when they breach the legal definition of harassment e.g. an action such as sending a text is not usually illegal, but is illegal when frequently repeated to an unwilling recipient. In fact, United Kingdom law states the incident only has to happen twice when the stalker should be aware their behavior is unacceptable e.g. two phone calls to a stranger, two gifts following the victim then phoning them etc.

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Wikipedia