Serial killers are not common, but they are fascinating because of the need to understand the phenomenon. There is no one definition of a serial killer, but there are some defining characteristics that set them apart from other murderers.

Serial killers present serious issues for law enforcement, due to the tendency for serial killers to blend in easily and appear "normal."

There is no one exact definition of a serial killer, from a legal, historical, psychological, or sociological viewpoint.

"In the past thirty years, multiple definitions of serial murder have been used by law enforcement, clinicians, academia, and researchers," (Blackwelder, 2010).

"There has yet to be a universally accepted definition for serial murder," Nelson (2004)

Definitions have differed over time, and differ according to context and culture (Nelson, 2004).

B. Definitions of serial killer differ on the grounds of:

Minimum number of murders: in some cases is 2, in others 3, and yet others the minimum number is 4. These discrepancies that can make a difference in crime statistics and how to approach theories of criminology and psychology. Right now the FBI sets the minimum number of kills to 2 but that is not always the case; Nelson (2004) notes that many definitions require 3 or more kills.

2. Types of motive/motivation classification. Sometimes they are defined as sexually deviant: as in the "offender's behavior and the physical evidence observed at the scene will reflect sadistic, sexual overtones," (cited by Nelson, 2004). However, "all serial murderers are not sexually based. There are many other motivations for serial murders including anger, thrill, financial gain, and attention seeking," (Blackwelder).

3. Temporal and geographic characteristics of the crimes. Blackwelder (2010) claims, "Most serial killers have a very defined geographic area of operation. They conduct their killings within comfort zones that are often defined by an anchor point." However, some serial killers might move around due to their lifestyle choice.

4. Psychological characteristics of the killer, including predilection for sexual fetish. However, some experts believe that the psychological characteristics of the killer are not important at all; that what is important is the pattern or behavior. The term serial killer...

Characteristics of the victim; including relationship between killer and victim.
(a) "Typically they seek to fulfill their elaborate and sadistic fantasies with innocent victims who conform to their imaginary script," ("Myths about Serial Murder," n.d.).

(b) Some serial killers kill victims they know; the importance is having control over choosing the victims.

(c) "Most choose their victims based on opportunity and accessibility. Simply, they prey on individuals who are vulnerable and easy targets," ("Myths about Serial Murder," n.d.).

6. There must be a "cooling off period," between the kills, during which the killer leads a seemingly normal life and does not kill. The "cooling off period" distinguishes serial killers form other types of killers. "The emotional cooling-off period is the most important factor in determining a serial killer," (Bonn, cited by Lohr)

C. There is a need to differentiate serial killer from mass murderer and other homicide patterns

1. A mass murderer commits four or more murders at one location, in one event. The event usually indicates a psychotic break in the killer's psyche (U.S. Bureau of Justice Statistics, cited by Lohr)

2. A cult or spree killing is also different from serial killing. Charles Manson is classified as a spree killer or a cult killer. "The FBI's general definition of spree killing is two or more murders committed by an offender or offenders without a cooling-off period," (Lohr)

III. History

A. Serial killing is ancient, and cannot be attributed to anomie in the modern world.

B. However, serial killing is also rare. Its astonishing, shocking, and strange nature makes it seem possibly more common than it is. "Less than one percent of all murders committed in a given year," are committed by serial killers (Blackwelder 2010).

C. Famous serial killers include

1. Jack the Ripper, in the Whitechapel area of London during the 1880s. He "sent letters to the police claiming to be the killer," giving some insight into the psyche and phenomenon (Blackwelder 2010).

2. Ted Bundy

IV. Current Stats/Prevalence: One Website indicates that the United States has the majority of the…