Many clinicians have long believed that racism is a type of Delusional Disorder. According to the Diagnostic and Statistical Manual of Mental Disorders, delusions are "fixed beliefs that are not amenable to change in light of conflicting evidence."(I find the DSM's definition of delusions somewhat humorous, since many people stick to beliefs that are cultural or religious despite overwhelming data indicating a lack of scientific evidence for these beliefs. Most of these beliefs are not dangerous, however; whereas some delusions can be dangerous).The DSM categorizes delusions by whether or not they are bizarre (not possible) and according to type, e.g. Erotomanic, Grandiose, Jealous, Persecutory or Somatic. Jealous, Persecutory and Erotomanic delusions can be dangerous. Some racist beliefs could be categorized as persecutory delusions.
After reading reports of the recent shooting in Charleston, South Carolina, I wondered if the perpetrator's thought content might qualify as delusional and persecutory. According to reports, the perpetrator, Dylann Roof, expressed thoughts that black people were "taking over" and were responsible for raping white women. There is no evidence in reality for these beliefs. Rapists tend to pick victims from their own racial group, and the percentage of black people in the US is not growing. Of course, people can have erroneous beliefs based on misinformation or ignorance rather than paranoia. I suppose it's possible Roof subscribed to websites or other sources of misinformation that promoted these erroneous beliefs. It's also possible they were simply inventions of his own mind, in which case they could be classified as persecutory delusions.
Some may find this discussion irrelevant in light of the fact that Roof apparently committed murder and his emotional problems aren't the point. Others might fear that examination of the perpetrator's mental state could lead to a conclusion of lesser responsibility. I disagree with these points of view. Before any incident, there is a chain of events. To prevent crimes and disasters, it's important to analyze the factors that led up to the event. Moreover, having a mental illness does not preclude responsibility for a crime. To be found Not Guilty By Reason of Insanity (NGRI), a person has to be shown to be unaware of the difference between right and wrong at the time of the crime. A rationalization for the crime does not count as a lack of awareness of right and wrong.
What, if anything, could have prevented the murders in South Carolina? Sadly, psychotherapy does not have a good track record in treating delusional disorder. The delusional person doesn't necessarily think that anything is wrong with him or her. Sometimes feelings of paranoia respond to anti-psychotic medications, but this treatment is only possible if the patient agrees to take the medication. What we do know is that most mental conditions can be exacerbated by stress. Unemployment or financial problems, or lack of social support, could exacerbate paranoid and delusional beliefs. According to reports Roof was occasionally living in his car, prior to the incident.
Roof was also voicing violent thoughts to his friends and some were aware that he had a gun. Yet, no one took action to prevent what in hindsight seems like the inevitable. I believe that a gun license should require psychological testing, which almost certainly would have revealed pathological and dangerous thought content in the case of Roof. One of Roof's friends reportedly removed his gun, but then put it back after fearing he himself could get in trouble for owning a gun. It's easy to see that some creativity on the part of Roof's friends might have averted the incident, but we can't rely on lay people who may have their own problems to intervene in these circumstances. We need to screen out the paranoid and delusional from gun ownership.