Most Mass Shooters Are Mentally Ill. Denying This Fact Only Leads to More Tragedy.
Denying that mental illness is not only a significant but potentially the most critical factor driving mass shootings does nothing but invite further tragedies. Discussions surrounding the motives for these acts of violence often prioritize sociological and ideological explanations while neglecting psychological factors. This dismissal of the psychological dimensions of mass shootings has contributed to the persistence of such tragedies, including two devastating incidents occurring just ten days apart: the Tops Supermarket shooting in Buffalo, New York, which claimed ten lives, and the Robb Elementary School shooting in Uvalde, Texas, where 22 individuals — 19 of them children under the age of ten — were killed. Many remain unaware of the 17 other mass shootings that took place in the ten days between these two events. When we fail to prioritize mental well-being — particularly for individuals experiencing violent symptoms of mental illness, such as persistent rage, aggression, or obsessive homicidal thoughts — we inadvertently signal to potential perpetrators that their symptoms and behaviors are either normal and acceptable or that there is no available support due to the stigma surrounding violent tendencies. This neglect increases the risk of their unresolved distress escalating into violent action.
Understandably, individuals who have mental illnesses themselves, as well as their loved ones, are often the most vocal in rejecting any acknowledgment that mass shooters may have a history of mental illness. Historically, society has heavily stigmatized mental illness, often unjustly associating it with violence. This broad-brush labeling has contributed to the mistreatment and misunderstanding of mentally ill individuals by both professionals and the public. The false belief that all violent individuals are mentally ill, though widespread, is misleading. While violence typically stems from some form of mental disturbance, this does not mean that all individuals with mental illness are violent. In fact, research indicates that the vast majority of people with serious mental illnesses are not violent — accounting for less than 5% of violent crimes in the United States (Peterson et al., 2022).
However, can one assert with absolute certainty that mass shooters are not mentally ill or that psychological disorders play no role in their actions? Given that there are hundreds of recognized mental illnesses and that nearly half of the U.S. population will meet the criteria for at least one such disorder during their lifetime (Peterson et al., 2022), dismissing the potential influence of mental illness on mass shootings seems premature. The general public often lacks a comprehensive understanding of mental illness — what constitutes it, how it is defined, and how it manifests in behavior. Despite this limited knowledge, many confidently assert that perpetrators of mass shootings are not mentally unsound in any way. Consequently, in the aftermath of preventable tragedies, discussions tend to exclude psychological factors, instead focusing almost exclusively on political and sociological explanations as the sole catalysts for such violence.
A more nuanced approach requires acknowledging the psychological dimensions of these crimes. Research has shown that while individuals with severe mental illness are responsible for a small fraction of violent crimes, the prevalence of mental illness among mass shooters is disproportionately high. Studies indicate that over half of mass shooters have been formally diagnosed with a mental illness, and when considering self-reported symptoms and behavioral indicators, approximately 67% of perpetrators exhibited clear signs of mental illness before their attacks (Lankford & Cowan, 2020). Furthermore, research suggests that a history of mental health issues correlates with increased violence among mass shooters, even when a formal diagnosis is absent (Yelderman et al., 2019). A federal report on active shooters identified mental health issues as the most common stressor in the year preceding an attack (Yelderman et al., 2019). Additionally, mass shooters with undiagnosed and untreated mental illness tend to inflict a higher number of casualties during their attacks (Yelderman et al., 2019).
Violence, whether condoned or not, often serves as an indicator of underlying mental distress. While not all individuals experiencing violent symptoms will go on to harm others, the stigma surrounding these symptoms and the refusal to acknowledge them as part of mental illness reinforce harmful misconceptions. This societal neglect conveys that those exhibiting violent tendencies do not require or deserve help, further isolating them. All forms of mental illness and their associated symptoms — no matter how distressing — warrant greater understanding, reduced stigma, and improved access to care and treatment. Addressing the mental health needs of individuals exhibiting violent symptoms can serve as a critical step in preventing tragedies such as the Sandy Hook and Stoneman Douglas High School shootings. By expanding mental health support and intervention efforts, society can work toward mitigating the occurrence of mass shootings and fostering a more comprehensive approach to public safety.
