Don’t Be Silly! You Can’t Assess Risk for Terrorism

Dr Michael Davis1,2,3

1Centre for Forensic Behavioural Science, Swinburne University of Technology, , Australia, 2Department of Psychiatry, Monash University, , Australia, 3Department of Psychiatry, The University of Melbourne, , Australia

The threat of terrorism is a seemingly major national security concern. Accordingly, State and Commonwealth Governments in Australia have enacted legislation that permits the post-sentence supervision and detention of terrorism offenders based on their assessed level of risk. However, the psychological study of terrorism is at best in its embryonic stages. This paper will argue that while instruments for assessing the risk for violence and sexual offending have demonstrated a modicum of predictive validity, the same cannot be said for the small but growing number of risk instruments developed for use with terrorism offenders (e.g., VERA-2R, TRAP-18, MLG, etc). None of the available tools have been developed in order to answer the questions posed by such legislation and none have been validated for such purposes. Moreover, it will be explained from a mathematical perspective that even if such a tool could achieve comparable classification accuracy to mainstream risk approaches, the extremely low base rate of recidivism amongst terrorism offenders would still make this a horribly flawed practice. Indeed, for every recidivist terrorist identified several hundred would need to be falsely detained as false positives. Accordingly, while short-term “hot” threat assessment of terrorism offenders is arguably possible with appropriate caveats, long-term “cold” risk assessment of terrorists, as requested by Australian legislation, is clearly not. Despite this mathematical reality, many clinicians have embraced these unvalidated instruments with uncritical zeal to provide risk assessments that have been accepted by the Courts. The ethical and professional implications of this practice will also be discussed.


Dr Michael Davis is a Forensic and Clinical Psychologist in full-time private practice. He is the Victorian Branch Chair, and National Chair-Elect, of the APS College of Forensic Psychologists. Dr Davis has adjunct appointments at Swinburne, Monash, and Melbourne Universities and is a consultant to the Victorian Institute of Forensic Mental Health (Forensicare). His practice is divided between clinical-forensic assessment tasks (particularly the assessment of risk, personality disorder, and sexual deviance) and providing behavioural investigative advice to police agencies. He has consulted with police in several countries across three continents and is the only mental health professional in Australia to be elected to membership of the International Criminal Investigative Analysis Fellowship. Dr Davis also serves as an Instructor to the Behavioral Analysis Unit of the FBI and is on the editorial board of the Journal of Investigative Psychology and Offender Profiling.