While every serial killer is different, there are certain signs that tend to be common to them. Many of these signs are seen well before adulthood, some even as early as childhood. Some of the major signs include a tendency for aggressive behavior, a tendency to engage in sadist behavior, an obsession with examples of behavior linked to serial killing, and a lack of empathy for others. Each of these four major signs will now be looked at in more detail.
One aspect of behavior that is common to serial killers is a tendency for aggressive behavior.
Aggression is defined as "behavior intended to injure another person" (Seamon & Kenrick 592). This aggression can be physical, for example, in the form of hitting another person. It can also be non-physical, for example, calling someone a hostile name. Aggression often begins as early as childhood. At this stage, it is normally seen via the way that the child responds to problems. For example, a child with aggressive tendencies will often respond to stressful situations by acting in aggressive ways. This can include shouting, yelling, and hitting. This action can be directed at the person's parents, teachers, or at peers. As children get older aggressive behavior continues. In school, some individuals begin to bully other children, some intentionally hurt others by name-calling or by using physical violence against others. Any of these kinds of actions are a possible sign of the person becoming a serial killer. Another possible sign is linked to the idea that there is an opposite to aggressive behavior, which is known as prosocial behavior. Some individuals at the adolescent age will already have an idea of how their behavior is judged as being wrong by others. This can result in them choosing to hide or repress their aggressive tendencies. For this reason, there may be no obvious signs of aggression. However, the lack of prosocial behavior can still be identified. Prosocial behavior refers to behavior that helps develop social relationships. This is considered to be the opposite of aggressive behavior. One author notes that, "aggression and prosocial behavior represent opposite kinds of problem-solving strategies that are learned early in life. If a child learns one mode well he or she does not tend to learn the other mode well" (Eron 440). This means that the lack of prosocial behavior is an indication that an individual has not learned other coping methods. Aggressive behavior can then become a key part of a person's behavior. The lack of prosocial behavior can be observed in many situations. For example, consider how an adolescent responds to a situation where they are arguing with another person. An individual that has developed prosocial behavior will be able to argue about the issue in a calm manner. An individual that has not developed prosocial behavior may not be able to remain calm. They may argue in a more heated manner. Another key issue is that they may not be able to handle the other person not agreeing with them. For a person that has developed prosocial behavior, they will often be able to accept that the other person does not agree and will not continue to force the issue. The same is not true for someone who has not developed prosocial behavior. They may be unable to let the argument go. At the same time, they will often act in a way that many would consider childish. Rather than continue to discuss the issue, they may become frustrated and storm off. They may also resort to actions like calling the other person names. In addition, the individual is likely to continue to focus on the problem and the person they are frustrated with. This may involve planning some type of revenge against them or developing a strong sense of hatred. In these cases, the chosen behavior of the individual is not an aggressive act, but is an alternative to one. In either case, it shows that the person does not have the ability to cope with conflict with others in the normal way. This type of behavior extends to how the individual forms relationships with others. An individual that will later become a serial killer may either form no social relationships or may form relationships based on abuse of power. These things are all signs that the person is not able to get along with others or fit into normal society like most people can.
There is also a strong link between serial killers and the practice of sadism. Butcher, Mineka & Hooley (431) note that many serial killers are also sexual sadists. A sadist is defined by the DSM-IV-TR as a person who has recurring intense sexual fantasies or behaviors that involve inflicting pain on another individual (Butcher, Mineka & Hooley 431). This type of sexual behavior can begin occurring in an individual's youth. This can occur in three ways. The first is that an individual may avoid forming relationships with the opposite sex. In this way, a lack of apparent interest in the opposite sex is one possible sign. The individual's sexual gratification may then come from fantasizing about hurting members of the opposite sex. Often times, this will occur without the individual physically experimenting with hurting others. Just like for non-sadists, exploring sexuality often starts as an individual process. For this reason, the second related way is that the individual may achieve sexual gratification via materials that support their sadist interests. One study of serial killers found that 75% of serial killers collect materials related to sexual violence. This includes books, films, and pornographic magazines (Butcher, Mineka & Hooley 431). This interest in sadist materials can begin in adolescence and can be a way that the person begins to explore their interests in sadism. It can also be a way that individuals begin to explore their tendencies toward violence. In some cases, the sexual exploration will go beyond just interacting with pornography. This can involve an individual forming abnormal relationships with the opposite sex. The future serial killer may establish relationships based on the abuse of power and the use of violence. The future serial killer may also become a rapist. It is also important to note that there is often a link between serial killers and rape with many serial killers raping their victims. While the serial killing may not begin early, raping women may. This then becomes a clear sign that the individual may later become a serial killer.
Another key point is that individuals that will later become serial killers will often begin to experiment with their own tendencies during their youth. This is especially seen during the individual's teenage years. One author notes the importance of this stage of a person's life saying that in the teenage years individuals set the patterns that will last until the end of the person's life (Petersen 1988, p. 584). For individuals who will later become serial killers, aggressive behavior often begins to develop in this stage. Another important point is that individuals are also looking for role models during this period. This is described by Erikson (52) who says that adolescence is a period where individuals are questioning who they are and trying to establish their own identities. Robinson (30) further describes this by saying that individuals "will watch and learn from others they look up to." For an individual that is going to become a serial killer, one clue to this is that they adopt an unusual role model. This especially includes adopting a role model that society in general has rejected as being negative. This can include another serial killer or a negative historical figure such as Hitler. In addition, individuals will often be drawn to books, films, or other materials that support their own tendencies. This is especially the case for films, with many serial killers having a strong interest in violent films, especially those involving murder. While violent films are generally popular, serial killers tend to respond in a more obsessive manner. Rather than watch a violent film once, they may watch a film hundreds of times. This often occurs because a serial killer is aroused by the idea of murdering someone. In this way, watching these films is a way that they are able to explore their own desires. At the same time, the process of watching these films increases their own desire to be the one taking action, rather than the one watching the actions. Finally, the individual will often see the killers in these movies as role models and mirror their behavior from them. This was the case for Ted Bundy, who raped and murdered over 30 women, all of whom shared a similar appearance. In Bundy's confession he revealed that he chose these women because he was trying to recreate scenes from slasher movies (Butcher, Mineka & Hooley 431). This shows that Bundy's attraction to these kinds of movies was one of the signs of…