At the risk of sounding like a weirdo, I have a large library of true crime books (approximately 300 books) and I have taken a few college courses on the criminal mind. You would be amazed at how many sickos are (or was until they were caught) are running around loose.
In all the books and studies I have done, the only thing that is consistant is that 99% are males and a small percentage have had rough childhoods. Women tend to kill people they know and love. Other than that, there isn’t anything that ties them together. Some serial killers have had wonderful childhoods and other severely abused children grow up to be caring adults who would never hurt a fly.
The FBI has made a profile of serial killers, although there are the exceptions.
Robert Scigalski of the FBI writes:
*"In most cases you will find a bad childhood. A large percentage exhibit a trend of cruelty to animals when younger.
There are two classifications of offenders.
Organized offenders are apt to plan their crimes, use restraints, commit sexual acts with live victims, use a vehicle to abduct or transport victims, and display control over a victim to induce the victim to show great bodily fear.
The organized murderer also is more intelligent and possessed job skills. He engages in “controlled” conversation with victims, hides bodies and follows new media accounts of his crime.
Organized offenders have a high birth order, often being the first born son of a family. Although the organized offender has an average or better than average IQ, he often works at occupations below his abilities, yet prefers skilled occupation. His work history is sporadic.
"Disorganized serial killers aren’t so smart and tend to leave weapons at crime scenes. The also perform acts on the dead and keep bodies around. The depersonalize or dismember victims and don’t use or have a vehicle for criminal purposes.
They tend to kill when the urge strikes them. The crime scenes are random and sloppy with their violence sudden, with very little conversation with the victim.
He is usually socially inadequate, often never married, lives alone or with a parental figure and lives to close proximity to the crime scene."*
It is my personal opinion that in some cases there are undiagnosed brain disorders that causes certain people to be more susceptible to become killers. I think that this may explain how some killers who have had wonderful childhoods still go one to become murders and why some abused children go on to become caring adults while others turn into killers. I think there are a certain chain of events that can trigger this disorder. I do not think this is true for every serial killer, I just think it may be true for some.
Oh, and JFTR - Dahmer did kill and abuse animals. He would decapitate them and then boil their carcasses. In fact, he decapitated a large dog and hung the body on a fence not long before killing his first victim.
