Real or Imagined? Evidence Concerning the Mental Health-Terrorism Nexus from Australian Terrorism Trials.

• Author: Shanahan, Rodger

As more individuals come before courts on charges relating to support for the Islamic State, additional reliable information has come to light about their backgrounds. A range of claims surrounding their actions have been tested during trial or agreed to as part of a plea deal, allowing terrorism researchers to rely on more accurate datasets to study certain aspects of attackers' background. This article uses data from Australian terrorism trials in the Islamic State era to examine the degree to which mental health conditions exist among terrorism offenders and whether there is any causal link between their condition and their offending. The article first outlines key previous scholarship on the mental health-terrorism nexus. Researchers have often had to rely on media reports, interviews with family members, or the offenders themselves to glean the presence of mental health issues; the challenges that this creates for reliability of the data are discussed in the second section of the article, with the author arguing that court proceedings and inquests by coroners provide more robust data than previous methods. The third section presents findings from such proceedings in Australia.

Previous Scholarship

In the process of radicalization, mental health may be simply one of a number of causative factors. The link between mental illness and Islamist terrorism, however, is an issue that has attracted a degree of media and academic attention over the years even though there is actually quite limited research regarding the subject. (1) There have been broader studies on the psychology of terrorism, including John Horgan's book of the same name. Yet, this research has been much broader than the jihadi terror problem set in its treatment of terrorism and the aspects of psychology that it addresses. The best-known study into the motivation of jihadi terrorists prior to the emergence of the Islamic State was perhaps Marc Sageman's 2004 Understanding Terror Networks, which examined 172 Islamist terrorists to gain an appreciation of their backgrounds, motivations, and means of organizing.

Rebutting the idea that terrorism could be explained by psychological factors, Sageman railed against the lack of empirical data regarding psychological research into terrorists. His analysis of psychological factors among the terrorist cohort was confined to a subset of 10 from his overall study group of 172. They were chosen because there was a greater degree of biographical information available for them, including court records. Sageman observed that there was an absence of any major mental disorders among his small sample of 10, thereby reinforcing the standing research view that there was no significant pattern of mental illness among terrorists. (2) As a consequence, a conventional wisdom emerged that terrorism was "basically another form of politically motivated violence that is perpetrated by rational, lucid people who have valid motives." (3)

After the emergence of the Islamic State, its concomitant attraction of Western Muslims, and increased focus on attacks against targets in the West, the desire to understand the motivation and background of an increasingly large problem spawned a range of more contemporary studies that sought to better understand the nexus between mental health and terrorism. The most recent work on this issue identified 25 studies, most of which occurred after 2013, that measured the rates of mental health problems amongst a range of violent extremists. (4) The prevalence rates differed significantly between studies, reflecting the different definitions of mental health problems to be included, data collection methods and sample sizes.

Some of these post-2013 studies began to challenge the belief that Islamist terrorists were "rational, lucid" actors. A 2017 Dutch study, for example, used a comparison of police records of known or suspected jihadis with the medical records held by several healthcare providers--one of these providers estimated the proportion of jihadis with mental health issues to be approximately 60 percent (of whom a quarter suffered from severe mental health problems), well above the general global population's rate of 25 percent. (5) (a) While this figure is initially alarming, it also appears anomalous, as generally speaking most research to date appears to support the contention that terrorists are not more prone to mental illnesses than the general population.

In a study published in CTC Sentinel the same year, Emily Corner and Paul Gill examined 55 terrorist attacks involving 76 individuals where media reports indicated there was a link to the Islamic State. Using this data, they found that psychological instability was present in 27.6 percent of the individuals, comparable to the current worldwide average. These results were noted as being "extremely preliminary" given they relied on data sources from the lower end of reliability. (6)

Research Challenges

Corner and Gill's reference to source reliability is one of the reasons why it has been difficult for researchers to reach a coherent or consensus view of the link between mental illness and terrorism. There are a range of challenges in researching issues surrounding mental health and terrorism. The first issue is establishing a consistency of what is being measured. Some studies examined terrorist sub-categories, such as suicide bombers or lone-actors, to better understand whether mental disorders were more likely to account, in part or in whole...