Tracing Motivations: A Comparative Analysis of Lone-Actor Terrorism and Rampage Shootings in North America and Europe Between 2010-2018

Lone-actor terrorism and rampage shooting events attract a substantial amount of interest and concern from scholars, the public, and the media. Empirical research on lone-actor terrorism from a criminological perspective to date is limited, and it is crucial to investigate what is known about these incidents to further our understanding of these relatively rare but extremely high-impact events. The current research aims to investigate key differences between lone-actor terrorists and rampage shooters on a wide range of characteristics, and seeks to explore whether there are similar underlying mechanisms for these events. Little is known about the comparative nature of these events worldwide, and the present study addresses this gap in knowledge by offering the first quantitative analysis of lone-actor terrorism and rampage shooting incidents in North America and Europe within the recent time period of 2010-2018. An open-source data collection strategy was employed and searches of online databases and additional materials were undertaken to gather information on incidents, which resulted in a comprehensive sample of 155 perpetrators who were responsible for 134 incidents. To compare characteristics between groups, a series of bivariate and multivariate tests were conducted through SPSS, which allowed for conclusions to be drawn based upon statistical analysis of the data. The current study found significant differences between groups on a wide range of variables. Results revealed that the majority of lone-actor terrorism incidents occurred across Europe, whereas rampage shootings were more likely to occur within North America. Rampage shootings were more likely to involve the use of firearms compared to lone-actor terrorism incidents, whereas lone-actor terrorism incidents were more likely to involve the use of explosives and vehicles. Additionally, lone-actor terrorists were more likely to commit an attack as a result of political and/or religious motivations, whereas rampage shooters were more likely to be motivated by emotional triggers, relationship and/or domestic issues, and personal grievances. These findings offer insights into the underlying mechanisms of these events and the various behaviours and experiences of lone-actor terrorists and rampage shooters. Future research into these areas could lead to important prevention implications, and could be used to monitor and reduce lone-actor terrorism and rampage shooting events.