The US Department of Justice Office for Victim's of Crime (OVC) defines stalking as "repeated harassing or threatening behavior by a person" and/or "....unwanted contact between two people that directly or indirectly communicates fear...", and issues the warning: "Stalking can become violent."
Single-Stalking crimes typically include a series of stalking incidents perpetrated by one person and that often appear to be innocuous when looked upon as isolated instances.
Group-stalking is perpetrated by a community, organization and/or multiple persons joined together against a chosen victim in a collective effort to defame, discredit, harass, threaten, isolate, terrorize and destroy the victim's life until the innocent person is imprisoned, confined in an institution, dead or otherwise rendered null and void.
Stalking by an individual is a potentially violent crime punishable by state law via felony charges, Temporary Restraining Order (TRO) or a letter ordering the stalker to Cease and Desist.
Group-stalking constitutes an organized conspiracy to commit a premeditated crime and punishable by Federal law under the Racketeer Influenced and Corrupt Organizations Act, also known as the RICO Act or RICO.