In general, how is a serial killer defined in criminology, including the typical patterns of behavior and the minimum number of victims required?
In criminology, a serial killer is generally defined as a person who commits a series of murders, typically with three or more victims, carried out over a period of time with a “cooling-off” period in between each crime. These killings are usually separate events, often involving similar methods or characteristics.
Key points to note:
- Number of Victims: While some definitions use three or more victims, others (including the FBI) may use two or more murders as the threshold.
- Timing: The killings occur over days, months, or even years, not all at once—this distinguishes serial killers from mass murderers (who kill multiple people at the same time) or spree killers (who kill multiple people in different places over a short period without a cooling-off period).
- Cooling-off Period: There is a period of time between murders in which the killer resumes their normal life; this is a hallmark feature.
- Patterns of Behavior: Serial killers often have distinct methods or “signatures” (modus operandi), such as choosing similar types of victims, using the same killing techniques, or displaying ritualistic behavior.
- Motives: Motives can vary and may include psychological gratification, a desire for control or power, or other complex reasons.
Overall, serial killing is characterized by its repetitive nature, a distinct pattern, and a psychological aspect that separates it from other forms of multiple homicide.