Whereas serial murder involves the killing of several victims over a period of time, mass murder involves the killing of several victims at one time and in one place. Though there have been a number of female mass murderers, the great proportion are male.
There are several Motivational Typologies:
- DISCIPLE — This type follows the commands of a charismatic leader, like the followers of Charles Manson. They fall under the “spell” of the leader, and desire nothing more than to please their leader. Victim selection is usually random or has some symbolic meaning known only to the leader. Spatial mobility is a possibility, but usually the murders are committed fairly near the location of the leader. Weapons of choice are usually hand weapons, but poison, nerve gas, biological, and other weapons of mass destruction are also possible. Rarely is the disciple dispatched on a suicide mission as the whole point is to live to strike again. Gang initiation and cult loyalty killings fall into this category.
- ANNIHILATOR — This type exhibits the most mental problems and typically launches into a burst of violence against those who share his home. Usually, it’s the oldest male child in the family who exhibits some early warning signs of bizarre behaviour They then kill everyone in the family at one time, even the family pet. They often commit suicide afterwards or are shot to death once police arrive. They may lie in wait for when more family members are expected to visit, or they may travel some distance to kill relatives who live away. Strangers are usually spared as victims of this attacker. Whatever reasons they have for their behavior is unknown.
- DISGRUNTLED EMPLOYEE — This type is often a former employee or someone about to lose their job. They are sometimes on medical or mental disability leave. They appear to enter and move around the workplace with a target in mind, but they almost always kill randomly and indiscriminately as they wander about. Often, this type has been a long-term employee, but it can be a new employee too. It’s believed they are lashing out at some perceived unfairness, although lax management can be just as much involved as strict management.
- PSEUDO-COMMANDO — This type is usually a stockpiler of guns, assault rifles, grenades, and other exotic weapons. Their attack is usually the result of careful planning and a desire to lash out against the world which is “not right” in some way. Victims are usually selected at random, and this type of offender may be quite geographically mobile. It’s believed that something about the social world these offenders inhabit may be criminogenic, but gun collecting in itself is not to be construed as any warning sign.
- SET AND RUN KILLER — This type appears to be motivated by a desire to “go down in infamy” because they will, for example, claim to have a bomb or explosive device attached to themselves and blow themselves up and as many people with them in a crowded location. They are called set-and-run killers because it has been discovered that their true intent, most of the time, is not suicide, but to set or plant the device somewhere on a timer and then be removed (run) from the scene when the explosion goes off. They have some similarities to the serial arsonist in this regard. Another variation is product tampering. This type of offender may inject or insert poison into products on the shelves of grocery stores, although the motivation in this case could be a grudge against some company’s product.