There is a drumbeat of demand for a new federal assault-weapons ban to prevent more tragedies like the one that happened in Connecticut. If we had not tried the experiment, you could honestly wonder if it would do any good. But the policy has been tried and found wanting.
In 1999, the National Institute of Justice published a study by criminologists Jeffrey Roth and Christopher Koper, “Impacts of the 1994 Assault Weapons Ban: 1994–96.” It examined the effects of the federal assault-weapons ban in its first two years of operation and found no statistically significant reduction in murder rates. “The ban did not produce declines in the average number of victims per incident of gun murder or gun murder victims with multiple wounds.” The study also was unable to find any clear evidence that it reduced murders of police officers. The reason was simple: So-called assault weapons were never commonly used for murders before the ban, and more conventional-appearing weapons were effective substitutes for criminal misuse. Any assault-weapons ban that does not ban firearms that are equally lethal (such as those many Americans already own) is ineffective.
What does work? Professor Stephen P. Segal’s recent study of murder rates and mental-treatment policy, “Civil Commitment Law, Mental Health Services, and U.S. Homicide Rates,” examined state-by-state murder rates and mental-health services and found that “less access to psychiatric inpatient-beds and more poorly rated mental health systems were associated with increases in the homicide rates of 1.08 and 0.26 per 100,000, respectively.” There was an even greater difference in the homicide rate between states with different involuntary civil commitment (ICC) laws. “Broader ICC criteria were associated with 1.42 less homicides per 100,000.” In short, states where involuntary commitment was easy had roughly a third less murders than states where it was very hard to civilly commit a mentally ill person.
The reason that more mental-health services and more relaxed involuntary-commitment standards make such a difference in murder rates is very simple: Mentally ill persons are disproportionately involved in violent crimes, including murder. As of 2002, about 26,000 inmates in state prisons across the United States who were convicted of murder were also mentally ill. A detailed examination of Indiana prison inmates convicted of murder found that 18 percent were diagnosed with “schizophrenia or other psychotic disorder, major depression, mania, or bipolar disorder.” Many of the random mass murders that have so plagued not only the United States but many other industrialized societies in the last few years were committed by persons with clear evidence of severe mental illness, usually schizophrenia.
If we are serious about reducing these relatively rare (less than 1 percent of U.S. murders are incidents of mass murder) but terrifying tragedies, we need to be looking at the root cause: untreated or inadequately treated mental illness. Focusing on the weapons may be good politics, but the experimental evidence suggests that it is bad public policy.
— Clayton E. Cramer teaches history at the College of Western Idaho. His most recent book is My Brother Ron: A Personal and Social History of the Deinstitutionalization of the Mentally Ill (2012).