How can extremists and terrorists be re-integrated into society upon their release from prison? What measures can be taken to minimize the risk of recidivism among this particular group of individuals? Over the past several years, these questions have been at the forefront of research on terrorism. Due to the large number of foreign fighters who have been drawn to the conflicts in Syria and Iraq, the potential risk posed by returnees and the increased number of people who provide tacit support to groups like IS, the reintegration question is now perhaps more salient than ever. Unfortunately, despite the importance attached to this topic by policy makers and academics there is a marked lack of evaluation studies that assess whether these programs are effective to begin with and – if so – what particular interventions or policies award them this efficacy.

Assessing whether reintegration programs for terrorist and extremist prisoners or suspects ‘work’ is no simple task. First of all, we must clarify what ‘success’ means in this context. In the Netherlands, research has shown that almost 50% of people released from prison will reoffend within two years. Would a similar recidivism rate be deemed acceptable when it comes to people (suspected of) involvement in political violence? Given terrorism’s considerable societal impact the answer is ‘probably not’. However, the difficulties of reintegrating ‘normal’ offenders suggest that setbacks will be inevitable when working with this politically sensitive group of individuals. An important first step toward assessing the efficacy of reintegration programs could be to conduct an independent investigation into the recidivism rates of terrorist and extremist prisoners in multiple countries. Once an ‘average’ recidivism rate has been established, it becomes possible to identify programs that under or outperform this figure, giving researchers a proxy for gauging their effectiveness.

Another difficulty is that evaluation studies will be hard put to work with control groups. Given the risk involved with the reintegration of extremist or terrorist detainees and suspects, it is highly unlikely that the go-ahead would be given for a study that purposefully does not subject part of those returning to society to a program designed to lower their chance of recidivism. Instead, evaluators will most likely have to rely on perceptions of effectiveness among program staff. Does the personnel involved in the actual reintegration work think their efforts are fruitful and if so, why?

These obstacles do not mean that evaluatory studies cannot be usefully conducted. In 2012, the Dutch National Coordinator for Security and Counterterrorism (NCTV) asked Leiden University to evaluate the roll-out of a new reintegration program aimed specifically at (former) jihadist terrorists and extremists that it had initiated together with the Dutch Probation Service (Reclassering Nederland, RN). The evaluatory study was conducted over the course of one year and described the program’s organizational implementation and the assumptions about how to achieve reintegration success that informed NCTV and RN’s approach. It also conducted a preliminary look at the initiative’s success. Although hampered in this last aspect by the issues outlined above, the study’s result provide a critical look at the Dutch efforts that can function as lessons learned for those looking to study or implement similar initiatives.

For those interested in learning more about this Dutch program, its preliminary effectiveness and the broader discussion about reintegration initiatives and how to evaluate them, the study’s findings have recently been published in Behavioral Sciences of Terrorism and Political Aggression.