Personality Assessment and Mass Murder
OK, the title of this post was admittedly a bit over the top to catch your attention. But there is an important connection here that I would like to explore in this post.
The alleged shooter in the Aurora, CO mass shooting, James Holmes, made a startling presentation at his arraignment. As you may recall, he appeared in court with his hair dyed flame red contending that he had no recollection of the shooting and even doubted that he was responsible. Meanwhile, subsequently, his attorney has offered statements that suggest that he may be laying the groundwork for an insanity defense. While most of the high-profile killers in recent memory have died at the time of killings, some of them survive and are captured. Holmes, Jared Loughner, the accused assailant of Congresswoman Gabrielle Giffords, and Nidal Hasan, the accused Ft. Hood shooter are all currently facing trial, and all will likely offer a defense based upon mental illness of some sort. Thus, personality assessment becomes an integral part of the criminal proceedings.
High-stakes forensic cases - especially criminal - are notoriously difficult to evaluate. Defendants have a powerful incentive to feign mental illness or at the least to exaggerate their symptoms. At the same time, there is an equally high index of suspicion such that prosecutors (and usually juries) are loathe to attribute the crimes to psychiatric illness. Research has shown that interviews alone are notoriously unreliable at determining real from feigned symptoms. Kenneth Bianchi, the notorious Hillside Strangler, was able to convince several psychiatrists that he suffered from Multiple Personality Disorder (now known as Dissociative Identity Disorder) until exposed by Dr. Martin Orne. Personality testing can be invaluable in helping make the differential diagnosis between malingering and genuine symptoms.
Several personality tests have been developed to ferret out attempts to malinger (fake) psychiatric symptoms. Most of these have been fairly well-validated, and can contribute to the assessment of defendants in high stakes cases such as the ones mentioned above. At the same time, more broad-spectrum instruments can help paint a picture of the defendant's personality and psychopathology that can aid the forensic examiner in understanding the motivation for the crime. John Hinkley, the man who attempted to assassinate Ronald Reagan out of an obsession with the actress Jodie Foster, was found not guilty by reason of insanity largely because of the psychological assessment performed by psychologist, Ernst Prelinger. On the other hand, often it is the testimony of psychologists who have tested the defendant that has punctured claims of insanity by demonstrating that the psychological tests either show no significant disorder or a strong likelihood of faking.
As the current batch of high-profile defendants work their way through the criminal justice system, it will be interesting to watch if and how psychological assessment is used to help determine the defendants' state of mind and ultimately their criminal culpability.