High-profile mass shootings can create lasting ripple effects, inspiring future attackers to mimic the crimes of their predecessors. A new study published in the Journal of Criminal Justice reveals that copycat shooters often share significant similarities with their role models, including demographic traits and the types of locations they target. Troublingly, nearly 80% of copycat attacks occurred more than a year after the original incident, with an average delay of approximately eight years, suggesting that the influence of high-profile mass shooters persists over long periods, making their actions a lingering threat that can inspire violence long after the initial event.
Past research has shown that extensive coverage of mass shooters can glorify their actions and inspire others to follow suit. This is evident in cases where attackers have explicitly named or modeled their actions after previous perpetrators. Despite the clear link between media exposure and copycat behavior, researchers Adam Lankford and Jason R. Silva noted that little empirical research has explored the characteristics that make individuals more susceptible to such influence or the extent to which copycat shooters mimic their role models.
“The notion that some people who commit mass shootings are not attacking for their own reasons—they’re copying a role model instead—is incredibly scary,” said Lankford, professor and chair of criminology and criminal justice at the University of Alabama. “It suggests high-profile attackers can have exponential effects on inspiring generations of new attackers. But before we conducted this study, there had been almost no empirical research on who is most susceptible to this type of influence and what behaviors they are likely to copy.”
The researchers compiled data on 205 documented cases of mass shooters who were influenced by prior perpetrators. They compared these copycat attackers to their role models across various characteristics, such as age, sex, race, and location type, and examined patterns in their crimes. To test whether these similarities were statistically significant, the team conducted 2,000 simulated matches, pairing real copycats with random perpetrators from a dataset of 857 public mass shooters and active shooters worldwide.
The study focused on public mass shootings and active shootings that caused at least one casualty between 1966 and 2022, excluding incidents linked to gang or domestic violence. To qualify as a copycat, evidence had to show a clear connection to a role model, such as references in manifestos, social media posts, or investigative findings.
Lankford and Silva found that copycat shooters are substantially more likely to share key demographic traits with the perpetrators they emulate, including age, sex, and race. For example, nearly all copycat attackers in the study (98%) shared the same sex as their role models, and 68% shared the same race. Additionally, 59% of copycats committed their crimes in the same country as their role models, further reinforcing the likelihood of geographic proximity in these connections.
“In the article we present a graph of the age differences between copycat attackers and their role models, and it looks remarkably like a bell curve or normal distribution, with the approximate midpoint and most common age gap being zero (which means the perpetrators were both the same age when they attacked),” Silva, an assistant professor at William Paterson University, told PsyPost. “Although we expected similarities, it was surprising how perfectly the age data fit our expectations.”
The researchers also identified patterns in the types of locations targeted and the outcomes of attacks. Copycats were nearly three times more likely to choose the same type of location—such as schools, places of worship, or commercial establishments—as their role models. Moreover, they were 39% more likely to experience the same outcome, whether that was suicide, lethal confrontation with law enforcement, or arrest. These shared characteristics suggest that copycat shooters often model their attacks on their role models in ways that go beyond mere inspiration, replicating specific aspects of their crimes.
One striking finding was the long temporal gap between attacks by role models and their copycats. On average, copycats struck nearly eight years after their role models, with almost 80% of copycat attacks occurring more than a year after the initial incident. This challenges the assumption that copycat behavior is a short-term phenomenon triggered immediately after high-profile shootings. Instead, it underscores the enduring influence of high-profile attackers, whose notoriety can resonate with potential copycats for many years.
“Many people fear short-term contagion and copycat effects, like the prospect that a mass shooting today will inspire another one tomorrow, and then the next day, and the day after that,” Lankford said. “But we found that approximately 80% of copycat mass shooters attacked more than one year after their role model, and the average delay was nearly 8 years. Anyone who notices their family member, friend, or acquaintance has developed an unhealthy interest in a past mass shooter should consider that a serious warning sign, even if that perpetrator attacked many years ago.”
Despite these similarities, the researchers found that copycat shooters tend to inflict less harm than their role models. On average, copycats killed ten fewer victims and injured 15 fewer individuals. This disparity could stem from various factors, including differences in planning, skill, or external circumstances, or it might reflect a phenomenon known as “generation loss,” where the replication of an original act loses its intensity or effectiveness over time. Regardless of the cause, the lower severity of copycat attacks provides a small but notable silver lining within an otherwise troubling trend.
“As society changes, mass shooting threats can change as well,” Lankford noted. “For example, there was a recent school shooting by a female perpetrator in Wisconsin who appears to have been inspired by male mass shooters. Our findings suggest role models and copycats usually have the same gender, so this was surprising. But it will be interesting to see whether she becomes a role model for future attackers, and if so, will they often be female copycats (as our study might suggest) or male copycats?”
The findings highlight the importance of addressing the role of media in perpetuating the cycle of mass shootings. When mass shooters receive extensive coverage, they are effectively rewarded with fame, which can inspire others who identify with their characteristics or grievances. Efforts to reduce this effect could include withholding the names and images of perpetrators from media reports, a practice already recommended by several organizations and campaigns.
“Scholars and public campaigns like ‘No Notoriety’ have suggested it is important to avoid glorifying mass shooters while still disseminating necessary news information,” Silva said. “Our findings directly support these efforts. Copycat mass shooters appear almost entirely dependent on the media coverage of high-profile perpetrators, along with social media, for the information that drives their obsession and imitation.”
The study, “Similarities between copycat mass shooters and their role models: An empirical analysis with implications for threat assessment and violence prevention,” was published November 2024.
