Not all aggressive behavior in humans can be called the result of some mental deviation, or, at least, a deviation as serious as a dysfunction of the violence inhibition mechanism and psychopathic predispositions. Some aggressive behavior, for example, self-defense, is completely natural based on ethological definitions and evolutionary data. Therefore, the question arises as to what the difference is between the aggressive behavior of ordinary people and that of psychopathic individuals
To answer this question, aggressive behavior must be divided into reactive and proactive forms. Reactive aggression manifests spontaneously or impulsively; it is not planned behavior and carries absolutely no goals other than causing harm directly within a conflict situation. Of course, it can be pathological, and sometimes it can be classified as violence from an ethological point of view. However, reactive aggression can also be completely natural non-pathological behavior, such as self-defense. In turn, proactive or instrumental aggression consists of achieving a specific result; it is the planned and motivated infliction of harm upon a victim. There is little reason to doubt the pathology and violent nature of behavior in which a person intentionally attempts to achieve something specifically by causing harm to other people.
As demonstrated by a vast number of studies, there is a strong link between a person’s level of psychopathic traits and the reactivity/proactivity of their aggressive behavior. For example, psychopathic criminals are more prone to violent attacks, and their aggressive behavior can be both proactive and reactive, whereas the crimes of non-psychopathic individuals are more reactive. This is especially true in the case of the most violent crimes, such as rape and murder. At the same time, less serious crimes, such as theft or burglary, can be committed with equal probability by both a psychopath and a non-psychopath. Similar results are shown in studies of the non-criminal population. Individuals prone to instrumental aggression are more psychopathic.
Even in the case of imprisoned murderers, higher levels of psychopathy are associated with greater proactivity or instrumentality of their crimes. In the case of clinical psychopaths, as much as 90-93% of murders are purely instrumental, without the slightest trace of reactivity. And even a criminal committing a single act of instrumental violence is already associated with an increased level of psychopathy. Furthermore, a current study of murderers sentenced to death in California demonstrates that individuals with low levels of psychopathy (less than 15% of the sample) often had no prior criminal record, repented for their deeds, and behaved according to judicial norms. Other individuals were prone to worse behavior. And five individuals (less than 1% of the sample) with the highest psychopathy scores were the most brutal criminals—serial sexual murderers.
These and many other data once again confirm that while not all aggressive behavior is a sign of a mentally unhealthy individual, the commission of violent attacks as planned and intentional behavior pursuing certain goals definitely demonstrates a dysfunction of the violence inhibition mechanism and psychopathic predispositions. Such people pose the greatest threat to every member of society, as due to their pathology, they are capable of using violence as a tool, which leaves ordinary people only the fate of the victim.
