Innovative Approaches to Safety: Exploring the Potential of TRAP-18

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Innovative Approaches to Safety: Exploring the Potential of TRAP-18

The insights presented in this blog are based on current published research. MHS disclaims the use and application of the TRAP-18 other than by qualified professionals and as intended. Further research is required to fully validate these initial research findings.

Since the early 1990’s, law enforcement agencies have faced significant challenges in addressing the evolving threat of lone-actor terrorism. The increase in low-tech, high-impact attacks poses a significant challenge due to their ease of execution and minimal planning requirements1. The surge in extremist activities further complicates the landscape, with attacks motivated by several different ideologies becoming more prevalent.

Navigating the complexities of targeted violence risk assessment

Recent trends indicate a concerning rise in lone-actor terrorism or violence involving adolescents. One significant factor is the ease of online radicalization, where young individuals are increasingly exposed to extremist ideologies through social media and other online platforms1. This digital environment allows for the rapid dissemination of radical content, making it easier for adolescents to be influenced and inspired to commit acts of violence.

Assessing the risk of targeted violence poses significant challenges for mental health, intelligence, law enforcement, and security professionals. One major hurdle is the complexity of threat assessment, which requires a multidisciplinary approach to understand a wide range of behaviors and indicators2. The rise of online radicalization further complicates this task, as the internet and social media platforms facilitate the rapid dissemination of extremist content, making it difficult for professionals to monitor and intervene effectively. Additionally, many individuals who pose a risk have underlying mental health conditions, necessitating close collaboration between law enforcement and mental health professionals to accurately identify and manage potential threats.

To help professionals mitigate and assess risk, MHS’ Terrorist Radicalization Assessment Protocol-18™ (TRAP-18) provides a structured framework for identifying and evaluating potential warning behaviors and characteristics associated with targeted violence.

Mitigating threats with the TRAP-18

The TRAP-18 is a tool used to help mental health, intelligence, law enforcement, and security professionals assess the risk of targeted violence, particularly lone actor terrorism.

The TRAP-18 consists of 18 indicators divided into two categories:

  • 8 Proximal Warning Behaviors: These are behaviors that are more closely related in time to a potential act of violence, such as pathway, fixation, identification, and last resort.
  • 10 Distal Characteristics: These are longer-term traits that may indicate a risk for engaging in proximal warning behaviors, such as personal grievance, ideological framing etc.

The tool is designed to organize operational data on a person of concern and assist in planning risk management strategies to reduce the threat of targeted violence.

Research on the TRAP-18 highlights its effectiveness in identifying and evaluating potential warning behaviors and characteristics associated with targeted violence. The TRAP-18 has demonstrated strong interrater reliability and predictive validity3. The tool’s indicators, which include both distal characteristics (e.g., criminal violence, mental disorder, ideology) and proximal warning behaviors (e.g., pathway, fixation, identification, leakage, last resort), are effective in assessing the risk of lone-actor terrorism3.

Identifying adolescent threats: The role of TRAP-18 in school violence prevention

In 2014, the author of the TRAP-18, Dr. J. Reid Meloy, and colleagues, published a study focused on distinguishing between school shooters and other students of concern, by focusing on identifying specific warning behaviors that could indicate an increased risk of targeted violence among adolescents. The study found that certain warning behaviors, such as pathway, fixation, identification, novel aggression, and last resort, occurred with significantly greater frequency in school shooters compared to other students of concern4. This study emphasized the importance of recognizing dynamic and superordinate patterns of behavior that indicate an accelerating risk of violence.

As the TRAP-18 was developed, it was used in scenarios focused on adult subjects involved specifically with terrorism. However, a recently published study provides significant insights into the application of the TRAP-18 in the context of adolescence, particularly through the case analysis of Nikolas Cruz, the perpetrator of the Marjory Stoneman Douglas High School shooting5. The study retroactively applied the TRAP-18 to assess whether it could be used effectively in cases of severe targeted school violence (STSV).

Key findings from the study include:

  • Proximal Warning Behaviors: The study identified six out of eight proximal warning behaviors in Cruz’s case, such as pathway, fixation, identification, leakage, last resort, and directly communicated threat. These behaviors were evident in Cruz’s actions and communications leading up to the attack, indicating the TRAP-18’s utility in identifying imminent threats among adolescents.
  • Distal Characteristics: Eight out of ten distal characteristics were present in Cruz’s case, including personal grievance, ideological framing, dependence on virtual communities, thwarting of occupational goals, changes in thinking and emotion, failure of sexually intimate pair bonding, mental disorder, and criminal violence. These characteristics provided a broader context for understanding the underlying factors contributing to Cruz’s radicalization and violent behavior.
  • Overlap with Terrorist Violence: The study highlights the similarities between the developmental pathways of school shooters and lone-actor terrorists, suggesting that the TRAP-18, originally developed for assessing terrorist threats, can also be applicable in the context of school shootings. This overlap underscores the potential for using the TRAP-18 to inform threat management strategies in educational settings.

The authors of the study call for further research to validate the TRAP-18’s effectiveness in real-time threat assessment among this age cohort and its potential integration with other threat assessment tools. Overall, the study supports the use of the TRAP-18 as a valuable tool for assessing and managing the risk of targeted violence among adolescents, particularly in school settings. The TRAP-18 provides a structured framework for identifying warning behaviors and characteristics that can help prevent future tragedies.

By identifying proximal warning behaviors and distal characteristics, TRAP-18 helps professionals in mental health, intelligence, law enforcement, and security evaluate potential threats effectively. As we continue to face evolving threats, integrating TRAP-18 into threat assessment strategies is crucial for enhancing public safety and protecting vulnerable populations.

Read more from MHS on preventing targeted violence among adolescents.

Have questions? Get in touch with a member of our team.

References

1 Winter, C., & Spaaij, R. (2021). Lone actor terrorism in 2019 and 2020: Trends and implications. In L. Close & D. Impiombato (Eds.), Counterterrorism Yearbook 2021. Australian Strategic Policy Institute.

2 Borum, R., Fein, R., Vossekuil, B., & Berglund, J. (1999). Behavioral Sciences and the Law, 17, 323-337.

3 Meloy, J. R., Goodwill, A., Clemmow, C., & Gill, P. (2021). Time sequencing the TRAP-18 indicators. Journal of Threat Assessment and Management.

4 Meloy, J. R., Hoffmann, J., Roshdi, K., & Guldimann, A. (2014). Warning behaviors discriminate between school shooters and other students of concern. Journal of Threat Assessment and Management, 1(3), 203-211.

5 Allely, C. S., Scheithauer, H., & Langman, P. (2024). Case analysis: Application of the Terrorist Radicalization Assessment Protocol-18 to the perpetrator of the Marjory Stoneman Douglas High School shooting in Parkland, Florida. Journal of Threat Assessment and Management. Advance online publication.

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