Definitions


The official FBI definition from the FBI Crime Classification Manuel (1992)

"Three or more separate events in three or more separate locations with an emotional cooling-off period between homicides."


It stresses

- Quantity. There has to be a minimum of three murders.
- Place. The murders have to occur in three or more different locations.
- Time. There has to be a "cooling-off period" between those crimes, either several hours, days or years.


A broader and more flexible and at the same time more accurate definition was formulated by the National Institute of Justice:

"A series of two or more murders, committed as separate events, usually, but not always, by one offender acting alone. The crimes may occur over a period of time ranging from hours to years. Quite often the motive is pyschological, and the offender's behaviour and the physical evidence observed at the crime scenes will reflect sadistic, sexual overtones."



Ten common characteristics of Serial Killers


Although it is very difficult to actually determine the very traits of "a" serial killer, the real-life profilers Robert Ressler and John Douglas of the FBI's Behavioral Science Unit along with the professors Ralph D'Agostino and Ann W. Burgess listed the following "general characteristics" of serial killers, based on a study:

1. Most of the serial killers are single white males.

2. They tend to be intelligent, with an IQ in the "bright normal" range.

3. Despite their intelligence, they tend to do poorly in school, have trouble holding jobs down, and often work as unskilled laborers.

4. They tend to come from markedly unstable familes, typically having been abandoned at an early age by their fathers and grow up in broken homes raised by a domineering mother.

5. There is a long list of criminal behaviour, psychiatric problems and alcoholic histories in their families.

6. They suffer signifcant abuse in their childhood - psychological, physical and sexual. Often the abuse is by a family member, commonly the father.

7. Because of their resentment towards an absent or abusive father, they have great problems with a male authority figure. Because they were dominated by their mother, they develop a great hostility towards women.

8. From an early age they manifest psychiatric problems and tend to spend some time in institutions as children.

9. Because of extreme social isolation and general hatred of the world they have high rates of suicide attempts.

10. They display an abiding interest in deviant sexuality and are obsessed with voyeurism, fetishism, and violent pornography.


It is of course dangerous to generalise or oversimplify the the characters and evolution of a "typical" serial killer as there are many exceptions to the rules. This is also why "profiling" a serial killer is a very difficult and tricky thing.



Three behavioural warning signs in childhood aka The MacDonald Triad


1. Enuresis or bed-wetting. A fairly common occurrence among children, this behaviour may be a sign of deeper pathology when it persists beyond the age of twelve. According to the FBI Behavioral Science Unit, more than 60 per cent of serial killers were still wetting their beds over the age of twelve.


2. Pyromania or fire-starting. Arson, or fire-setting, can be an early manifestation for a fondness for destruction. David Berkowitz - who laid hundreds of fires - was in his childhood so obsessed with fire that it earned him the nickname "Pyro".


3. Precocious sadism or animal torture. In the case of many violent criminals, animals were the first victims of this behaviour. Young Jeffrey Dahmer liked to nail live bullfrogs to trees, and cut open goldfish/stray cats and dogs to see how their innards worked.

The Abc Of Serial Killers	Figures and Stats
Webpages
The Top Ten...
Allusions
Types of Multiple Killers
Behaviour & Classification
Psychological Phases
Why They Kill
List of Serial Killer by Country
Serial Killers in Popular Culture