Because of the growing number of requests for profiling services in the 1980s, the FBI's Behavioral Science Unit made their services available to law enforcement nationwide through their Violent Criminal Apprehension Program (VICAP)--which maintains a nationwide network of computer databases dedicated to taking violent offenders off the streets as quickly as possible.
The VICAP Crime Analysis Report runs for ten pages of detailed law enforcement reporting for each murder. Factors such as age, gender, occupation, intelligence, acquaintance with the victim, residence, mode of transportation, modus operandi, ritualistic behavior, victim characteristics, and offender characteristics are recorded and entered into their database.
When two or more murders have been committed over time by the same person(s), a dynamic synergistic comparison can give investigators a systematic look at the presence or absence of evidence, the crime scene signature, the comfort zone of the killer, and the possible motives for the murders. Other indicators such as emotional intensity, the rationale for the murders and any number of factors that stand out to investigators can help law enforcement identify offenders. Criminal profiling gives investigative agencies the ability to connect details, recognize patters of offender behavior, and review national fingerprint and DNA databases which facilates the work of narrowing down suspects.
The intent of crime scene investigation and psychological profiling is to identify the key elements of the scene and the behavioral factors related to serial killers--enabling homicide investigators to prioritize leads and apprehend offenders before they can kill again. A developing composite profile does not provide the identity of the offender but merely indicates the type of person most likely to commit such a crime having these characteristics. One researcher, Geberth (1981), found that a murderer’s behavior and personality is reflected in the crime scene “much the same way as furnishings reveal the homeowner’s character.” Sexual homicide crime scenes reveal information about the killer’s behavior and how he furnishes his mind.
When crime scene characteristics are combined with profile characteristics, a composite picture of the behavioral traits of the offender begins to take shape. With serial killers, the profile comes into sharper focus with each new victim. From these elements, investigators are able to draw assumptions about the killer, but they need to be always on guard against tunnel vision—making conclusions that place limitations upon the investigation.
The BSU study discovered that most serial killers share many of the same formative experiences growing up:
- They had a history of being bullied or socially isolated as children and adolescents.
- They often engaged in petty crimes like theft, fraud, or vandalism.
- They are practiced liars.
- Many come from unstable families and have experienced a serious family disruption like divorce, separation, or a breach in the parent/child relationship.
- Many have a history of being abused emotionally, physically, and/or sexually in their youth by a family member.
- They often manifest attachment disorder due to early childhood trauma like violence, neglect, rejection, or pervasive alcohol or drug use in the home.
- They suffer from low self-esteem and retreat into a fantasy world where they are safe and in control.
- They are fascinated by fires and fire starting.
- And they often show cruelty to younger children and/or small animals.
Additional common traits of serial killers documented by the BSU were:
- A serial killer’s motivation is usually psychological gratification of some sort.
- They have a compulsive need for power and control over their victims.
- They suffer from mental illness with psychotic episodes and have mental illness or alcoholism in their family backgrounds.
- They have a passion for throttling which leads to overkill.
- They often display a blood lust by mutilating, dismembering, or disemboweling their victims.
- They have an overwhelming desire to inflict pain and terror, and many violate the bodies of victims with foreign objects.
- They are predators of victims weaker than themselves: children and defenseless women in particular.
- They lack remorse or guilt and project blame upon their victims.
- They suffer from impulsivity and are oversexed with intense sexual frustration.
- They have fits of self-pity and resentment.
- They often begin their crimes with peeping in windows and home burglary--which often escalates to rape and murder.
- They are compulsive liars and petty thieves.
- They usually stalk their victims but will take advantage of crimes of opportunity.
- They often take trophies from the crime scenes, photos, or body parts as souvenirs to relive their orgies of depravity.
- They often wear a mask of sanity in public for protective coloration.
- Their boundaries between fantasy and reality are lost.
- Their fantasies turn to dominance, control, sexual conquest, violence, and finally murder.
Not every serial killer fits each one these traits, but it is striking how consistently many of these traits appear in the profiles of every known serial killer.
These common characteristics help investigators form a composite picture of an offender. Drawing conclusions about a suspect from profile characteristics is as much art as science, and it takes a trained eye and a bit of luck to pay dividends, but when done properly, the likelihood of catching a serial killer is greatly enhanced.