Almost all of them had some kind of psychological disorder, and many were declared criminally insane. All the killers had a compulsion to continue killing. None of them stopped with one or two victims, in fact, the more they killed the more they wanted to kill. In addition, most of the male serial killers became increasingly violent and disturbed as they continued to kill. Authors Fox and Levin state, "It is commonplace for serial killers to increase the level of brutality as they get bored with less vicious behavior and as they grow more comfortable with murder. It is also not unusual for them to branch out to more respectable victims as they become convinced that they are smarter than the police and will never be apprehended" (Fox, and Levin 76). Most of the killers admitted to what they had done and knew how many people they had killed. Some almost seemed to take pride in what they had done. The only killer never to admit what he did is Randy Kraft.

Many of the killers firmly believed their victims "deserved" to die, somehow. Wuornos believed she had been "raped" and killed in self-defense, even though she worked as a prostitute. For some reason, Toppan and Terrell both felt their elderly charges would be better off dead, and Shawcross believed he was doing society a favor by murdering prostitutes. Kraft never admitted his murders, and so, he never took responsibility for the killings or said why he killed. They all tended to dehumanize their victims as well, and seeing them as deserving to die helped in this dehumanization process.

Most of the killers seemed like fairly normal middle class people. They held down jobs and some were homeowners. The women were dysfunctional throughout their lives, although they seemed to have somewhat less abusive childhoods than the men did. The women were also all mentally ill in some way. The men seemed to be mentally ill because of the enormity and depravity of their crimes, as well. Dahmer, Shawcross, and Kraft all used the insanity plea during their trials. Shawcross was found sane, and is still in prison. Dahmer was murdered in prison, Kraft is awaiting execution on death row in California, Wuornos was executed in 2002 in Florida, Tonnan died in an insane asylum, and Terrell is also in prison for a 65-year sentence.

The men in this group were certainly more violent and depraved than the women in their methods of killing. All the men, and only one woman, were sexual predators who victimized people for sex and sexual fantasies. Dahmer, Shawcross, and Kraft all brutalized their victims before and after they killed them and their brutalizations were horrific even to police investigators. Dahmer cannibalized his victims, Kraft tortured his, and Shawcross brutally mutilated the corpses of his victims. Their depravity far outweighs the women. The two nurses, Toppan and Terrell simply injected their victims with lethal doses of drugs, while Wuornos shot her victims several times, but did not mutilate them in any other way. The women were clearly as disturbed as the men were, and thought their victims deserved to die, but they were not nearly as grisly as the men in their murder techniques. This may stem from the fact that in society, women are generally less violent than men are and less open to violence. Men are raised to be more violent and "in control," and men fill most of the roles in society where violence is condoned, from fighters, boxers, police officers, hunters, and detectives, to soldiers and bounty hunters, men fill most of these roles, because it is more socially acceptable for men to be violent. Women are usually not raised to play soldier or war, and it is not as socially acceptable for women to engage in violence. Most women do not have that background, and so, their crimes tend to be less violent and depraved.

All of these killers seem...

The FBI has developed these profiles after years of studying serial killers. Another author notes, "Disorganized crimes, in contrast, are not planned, and criminals leave such evidence as fingerprints and blood. Disorganized criminals may be young, under the influence of alcohol or drugs, or mentally ill" (Winerman). All of the killers left behind clues, from bodies and body parts to blood, photographs, and other clues to their crimes. When Kraft was stopped, he was drunk, driving erratically, and had a body in the car next to him. Dahmer cruised bars and drank before he picked a victim; in fact, he was discharged from the Army because of his excessive drinking. The women were all judged insane by the courts. Therefore, all of these killers match the profile of the disorganized criminal. As another author notes, "The FBI's Behavioral Sciences Unit's strictly behaviorist classification of serial killers into the categories 'organized' and 'disorganized' redirects attention from motive or gender to something like preparation and neatness" (Seltzer 121). While all the killers were certainly prepared, they were disorganized in that they left evidence, were often mentally ill, and some relied on drugs or alcohol to motivate their killing.
The two nurses seem to fit the profile of the "angel of mercy" female serial killers. Wurnous may have seen herself that way as well, since the men had "raped" her and they deserved it. These angels of death see themselves as committing God's will somehow, and that they are sending their victims on to a better place. Since almost all their victims were elderly, they may have actually believed this in their own twisted minds. These profiles are only used for female serial killers, and the other is the "black widow," who often murders family members or acquaintances for financial gain.

Finally, people who have studied the minds and motives of serial killers believe they share so many commonalities that they should be easier to spot in society. Another author notes, "These are basically cookie-cutter people, so much alike psychologically I could close my eyes and be talking to any one of them,' says Dr. Morrison. 'They are phenomenally alike in the way their psychology is set, the way they function, and how they're misdiagnosed'" (Methvin). The profiles devised by the FBI have been remarkably accurate in predicting who serial killers turn out to be. As this essay shows, all of these killers had many commonalities, including psychiatric problems that often stemmed from a troubled, abusive youth.

In conclusion, these men and women prey on the most vulnerable members of society, and often do it in the most depraved and violent manner. They are psychopaths, who get a high from killing, and rationalize it by choosing victims they can dominate who somehow "deserve" to die. The more scientists and psychologists learn about these people, the easier it will be to spot them and arrest them before they can kill again.