Feb 04, 2021

Good Practices in Risk Assessment for Terrorist Offenders

Issue Paper from InFoEx Workshop, Berlin, March 16-17, 2020
Debatte über islamistischen Extremismus und Terrorismus
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In November 2019, two people were stabbed to death and three wounded in an attack near London Bridge. One year later, four people were killed and more than 20 injured in a shooting in the historic city center of Vienna. Both attacks were carried out by terrorist offenders recently released from prison. Several other incidents in recent years also involved former terrorist convicts. This brings the issues of risk assessment and management to the fore of the debate on Islamist extremism and terrorism.

Please note: The online version of the text does not contain footnotes. To see the citations, please download the PDF version here.


Executive Summary

Key Recommendations


Factors in risk assessment and management

Defendant and offender management

Assumptions and false compliance

Spotlight Germany: risk assessment tool RADAR-iTE

Experiences from other fields




In November 2019, two people were stabbed to death and three wounded in an attack near London Bridge. One year later, four people were killed and more than 20 injured in a shooting in the historic city center of Vienna. Both attacks were carried out by terrorist offenders recently released from prison. Several other incidents in recent years also involved former terrorist convicts. This brings the issues of risk assessment and management to the fore of the debate on Islamist extremism and terrorism. While European countries face similar challenges in assessing and managing the risk that violent extremists represent, approaches have differed. Over recent years, a myriad of different risk assessment tools has been developed, such as VERA-2R in the Netherlands or RADAR-iTE in Germany. Various approaches exist to dealing with (potentially) highly radicalized individuals both within and outside a prison context.

An international digital workshop in March 2020, which took place as part of the International Forum for Expert Exchange on Countering Islamist Extremism (InFoEx), addressed the issue of assessing the risks represented by highly radicalized individuals and supporting their deradicalization during their time in prison and after release. The workshop was organized by the German Council on Foreign Relations (DGAP) in cooperation with the Federal Office for Migration and Refugees (BAMF) and its governmental and civil society network partners; several external experts offered their insights on challenges and good practices.
These findings lead to the following key recommendations for assessing and managing risk:



1. Consider traditional risk factors for offenders when assessing the risk of violent extremism, such as adversity (for instance a difficult family background), having experienced distress and trauma, or a criminal history. Mental health should also be considered relevant for risk assessment. Any mental health issue should be clarified. For terrorist offenders, personality disorders seem to be more of an issue than severe psychopathologies.
2. Develop individualized interventions. Terrorist offenders are a heterogeneous group and have multiple reasons to engage or disengage. A one-size-fits-all program will not be specific enough to address the variety of (de)radicalization factors. A mentoring program can provide individualized support, especially during the critical time just after release.
3. Reduce handovers and streamline offender management. Terrorist offenders who enter the criminal justice system tend to pass various points of contact and go through many handovers from one agency to another. All relevant cases should be managed through one contact point – either a single actor or institution – to ensure coherence and continuity. Close cooperation with national and municipal authorities and community actors should be ensured even before release.
4. Conduct more research on false or disguised compliance. More evidence-based research is needed to detect whether individuals only pretend to be disengaged and deradicalized. Additional research is also required to validate the assumptions of risk assessment tools.
5. Learn from existing experiences in other fields. There are certain challenges that set sex and terrorist offenders apart from other offenders, for example the danger that a relapse can represent for others as well as the individual itself and the experience of rejection. A long-term accompaniment of terrorist offenders similar to existing programs for sex offenders may prove helpful. 



Whenever a recently released terrorist offender carries out an attack – for instance, in November 2019 on London Bridge, in February 2020 in the London suburb Streatham, or in November 2020 in the Vienna city center – the question of how to assess and manage risks takes center-stage in the debate about Islamist extremism and terrorism. Such incidents demonstrate dramatically how difficult it can be to evaluate whether an individual may be likely to engage in violence and to react appropriately. Affected countries respond differently. The United Kingdom, for example, quickly passed retrospective legislation to end automatic early release of terrorist offenders after the stabbing of two people in Streatham. Austria is currently debating the extension of preventive (custodial) measures for terrorist offenders who have served their sentence but are still considered radicalized.

In this context, experts working on the tertiary prevention of Islamist extremism benefit from discussing common challenges and sharing good practices from their respective countries. This issue paper presents results of expert opinions from the fifth InFoEx workshop which took place in March 2020. Originally, the workshop had been planned as a personal exchange between international practitioners, researchers, and policymakers in a trust-inspiring setting in Berlin. However, restrictions imposed because of COVID-19 made it necessary to change to a digital format at the last minute. As a result, 30 participants from Belgium, Denmark, Germany, the Netherlands, and the United Kingdom met online. This paper presents good practices on assessing risk and dealing with highly radicalized individuals in the context of Islamist extremism as discussed during the event. They are not to be understood as the participants’ agreed opinion but as a summary of the different experts’ inputs

Risk assessment management for violent extremists 

Risk assessment normally refers to specifically designed instruments used to gage the likelihood of a person endangering public security. This is done with the help of established criteria; the purpose is to allow the prioritization of resources. Well-known examples include VERA-2R (for example used by trained governmental and civil society actors in the Netherlands), ERG22+ (used by trained forensic psychologists and experienced probation officers in the United Kingdom), and RADAR-iTE (used by police in Germany). At the same time, prevention workers have also developed a portfolio of methods to decide which prevention measures to implement and when to report a person to the security agencies. Most existing risk assessment tools assume that, given enough information and sufficiently specific criteria, the security risks that an individual represents can be ranked according to a scale. This makes it possible to allocate resources accordingly, adopt specific measures, and compare profiles. 

Several problems remain, however, for example regarding “false positives” – if an individual is erroneously assessed as representing a risk of engagement in criminal behavior – as well as “false negatives” – if an individual is assessed as representing little or no risk but then plans and/or carries out an attack. Other difficulties include the selection of factors to be considered, the extent to which mental health issues contribute to a higher risk of engaging or re-engaging in violent extremism, and the possible stigmatization because of criteria that flag religious practices. There are also calls to include more evidence-based research on indicators of radicalization and to continuously evaluate and validate risk assessment tools to make them empirically and theoretically sound. 

Distinct approaches exist to managing inmates who have been convicted for terrorist offenses or are considered radicalized. For example, France and the Netherlands have opted for placing terrorist offenders separately (‘containment’), while Germany and Austria decided to disperse them among the regular prison population (‘dispersal’). In addition, staff working in the criminal justice system and prevention workers must develop and implement effective approaches to dealing with individuals identified as radicalized or highly radicalized. Common challenges include overcrowding of prisons, lack of training for prison and prevention staff, and false compliance, as in the case of the Vienna attacker who had been participating in a deradicalization program.

Despite different approaches and structure, two questions are relevant for all countries: First, how can criminal behavior be predicted, and how can the security threats related to violent extremism and terrorism be identified? And second, what are the consequences when dealing with potentially highly radicalized individuals both from a security and a tertiary prevention perspective? To address these and other challenges, examples of good practices that were presented at the workshop are summarized in the following chapters.



Both research and practical experience have demonstrated that multiple factors contribute to radicalization and that individuals have multiple reasons for engaging in violent and non-violent extremist activities. Risk assessment tools are expected to accurately capture these factors and provide indicators that reliably predict behavior. To support rehabilitation and reintegration, tertiary prevention workers must not only understand and address the factors contributing to a person’s radicalization. They must also strengthen protective factors.

  • One good practice mentioned was to include mental health among the many factors relevant to risk assessment and management. After 9/11, an analysis of the terrorist offenders revealed that they had a relatively high educational background and were not much different from the general population in terms of mental health. Consequently, traditional risk assessment tools were not considered relevant to cases of terrorism, and mental health issues were temporarily removed from risk assessment instruments like VERA (Weenink 2019, p.130). More recently however, practitioners and researchers have come across a higher level of mental health issues when dealing with terrorist offenders. Hence, new versions of VERA-2R are now incorporating mental health issues through “additional indicators.”
  • It was also considered important to clarify the term “mental health issues.” One expert shared his experience that while classic severe psychopathologies seemed to be more common with lone actors, personality disorders were more common more common with other terrorist offenders. According to preliminary results from research on the terrorist offender population in Belgium, the level of personality disorders was comparable to the general prison population but higher than in the general population.
  • Regarding other factors, some experts argued that traditional risk factors for offenders remain important for assessing the risk represented by violent extremists. Experiences from a Belgian prison indicated that many terrorist offenders have a criminal history and a difficult personal background; substance abuse and a low IQ also play a role. Another example mentioned was the result of two explorative-descriptive studies based on Dutch police files. The author, Anton Weenink, looked at the background of 140 (in 2015) and 319 (in 2019) extremists who had traveled or attempted to travel to join the Jihad. These individuals constituted a “new group,” as only ten percent had been known to be radicalized. They had “on average relatively high levels of adversity, distress, trauma, criminality, and mental health problems as compared to their age-matched peers” (Weenink 2019, p.137). With these findings in mind, one expert argued that focusing on ideological change might not be the best way. Instead, it was more important in terms of a frontline assessment to identify warning behaviors, when an individual with a known affinity for extremism and a history of violence is confronted with a serious stressor. Another expert recommended to consider “emotion” as a core element of radicalization. One should not just focus on what is being said but how it is being said. 
  • As terrorist offenders are a heterogeneous group, experts stressed that using a generic formula for interventions would fall short of addressing the various profiles. An intensive study of the offender’s biography and his or her behavior during their time in prison should be used to develop individual approaches. For example, based on research showing that terrorists do not have unifying demographic similarities, the UK developed the Healthy Identity Intervention (HII) to prevent extremist crime and provide methodologies to assess the risk of extremist crime (NOMS 2013, p.2). HII uses an individualized psycho-social approach focused on helping offenders disengage from extremist causes. However, one expert voiced concern about its applicability to individuals who joined or attempted to join the so-called Islamic State, since the intervention had originally been developed for Al Qaeda offenders ten years ago.



From the day a person is remanded in custody awaiting trial to his or her last day of probation, many actors and point of contacts are involved in offender management. These include security agencies, the judiciary, prison personnel, rehabilitation staff, and probation officers. In the case of terrorist offenders and radicalized individuals, prevention workers from civil society organizations or governmental exit programs are often added to the list. With so many different actors involved, experts working in the field of prevention of extremism warn that the lack of a coherent offender management poses a problem. For example, experience showed that there were too many handovers from one actor or agency to another, especially if terrorist offenders were expected to be moving toward rehabilitation. Important information could get lost due to this lack of coherence. In addition, a relationship of trust between the inmate and a counselor or mentor would have to be built over and over again. 

Experts also stressed that the prison environment did not exist in a vacuum but was influenced by developments outside the prison walls. For example, a British expert shared his experience according to which released offenders tended to return to both their former social networks and socioeconomic conditions. They were also facing challenges when trying to reintegrate into “mainstream society” because of their status as former convicts. Especially if released terrorist offenders returned to the community that had played a role in their crime and/or radicalization, they might engage or reengage in violent extremism and/or reoffend. Given these challenges, the following approaches were considered helpful: 

  • To reduce the number of handovers and streamline offender management, several experts recommended a more coherent approach involving all relevant actors throughout the whole process. At least one permanent contact person per individual should be designated. Others went further and recommended setting up a single unit which would bring together representatives of all relevant agencies to deal with every aspect of managing terrorist offenders. All terrorist offenders as well as offenders considered radicalized or at risk of radicalization should thus be managed by one contact point only – either a single actor or institution – to ensure coherence and continuity.
  • In addition, establishing transparent cooperation based on trust and clarity of roles and responsibilities between the different actors was considered crucial. Similar criteria should apply to the relationship with the client or inmate: The objective should be to establish trust and to be transparent about one’s role.
  • A good practice shared by a Danish expert to strengthen coherence in offender management and develop individualized approaches was a mentor program for radicalized inmates. In Danish prisons, individuals who have attracted an operational interest concerning radicalization or violent extremism – currently about 70 individuals or 1.6 percent of the total prison population – are assessed according to four different categories (0 representing almost no risk and 3 for the highest risk). An appropriate balance of soft and strict measures is then agreed, as is a close cooperation between national and municipal authorities outside the prison context. For example, individuals in category 3 cannot be released on probation and must serve their full sentence. Apart from psychological or therapeutic assistance, they can be assigned a mentor as part of the “Back on Track” program: Specially trained mentors accompany these persons during their remaining time in prison and after release. Mentors are recruited from a broad range of backgrounds, for example from prison and probation, police, and social work. Both mentors and case workers also provide feedback for an on-going risk assessment of the individual in question. So far, the experience with this program has shown that it is possible for a mentor to establish a stable relationship with the inmate for the whole duration of the prison term and to better support his or her reintegration into society after release. Mentors contribute to the coherence of offender management by supporting the authorities when dealing with the inmate or former inmate and coordinating with his or her family and community. 
  • Another good practice from Denmark that was shared during the workshop referred to the situation when highly radicalized individuals are not willing to engage with prison staff and case workers or mentors, especially in the case of returnees from Syria and Iraq. Similar to the Belgian experience, a Danish expert argued that in these cases, it seemed more effective for prevention workers not to focus on ideology and cognitive change but to start with other aspects of rehabilitation and resocialization, for example supporting access to education, employment, or treatment for addiction.
  • Regarding the merging of approaches and cooperation of actors from within and outside the prison system, one expert recommended stronger community involvement. For example, the case management unit mentioned above could be involved in developing long-term and trust-based relationships with local authorities and communities as well as the individual’s family. The expert suggested that community actors could then be more effective about assisting the protective services (those charged with preventing mistreatment, self-neglect, or exploitation of an at-risk person) and other services supporting the rehabilitation and resocialization of released detainees. However, questions remained open of where this unit would be located and which actors within the prison and the community would be involved to what extent.  



Attacks like the ones in London or Vienna raise the question of how one can determine if a person is only pretending to be deradicalized and disengaged from violence. 

  • Researchers recommended conducting more research on false or disguised compliance. One expert at the workshop stressed the importance of being engaged from the very beginning of an individual’s time in custody to accurately understand motivations, the path leading to violent extremism, and possible ways for that person to disengage. 
  • In this context, risk assessment tools would benefit from more evidence-based research, for example on the theoretical understanding of radicalization processes, concrete indicators, and base rates as well as success rates. Research is already increasingly focusing on the predictive qualities of risk assessment tools. 
The risk assessment tool RADAR-iTE was developed from 2015 by the Federal Criminal Police Office (Bundeskriminalamt or BKA) in cooperation with the working group on forensic psychology of the University of Konstanz. German law enforcement has been using the first version of the tool since 2017 and its revised version RADAR-iTE 2.0 since May 2019. The tool’s objective is to assess the likelihood that an Islamist (who is known to law enforcement) will carry out a politically motivated and serious act of violence. As part of a larger risk management process within the German police, RADAR-iTE is initiated when state police rate an individual as a “potential terrorist.” First, state police establish a “case chronology.” Several risk and protective factors are used to capture the individual’s professional and social situation, possible social and psychological anomalies, violent behavior in the past, suspicious stays abroad, and criminal history. Based on this information, a number identifying the specific degree of risk (moderate or high risk) is allotted. The BKA team, together with psychologists and experts in Islamic studies, then establishes a detailed “individual threat assessment.” Finally, it discusses the results with the relevant agencies to agree a common concept, decide on the right approaches, and adjust the measures so that resources can be prioritized. For example, the BKA may ask exit counselors to reach out to the individual.
Germany is currently developing another version of the RADAR-iTE to be used for right-wing extremism and terrorism.



When aiming to improve approaches to terrorist offender management, experts argued that it was worth considering experiences from other fields. For example, there are certain challenges that set sex offenders and terrorist offenders apart from other types of offenders. These include not only the danger that a relapse may represent for others as well as the individual itself. Both sex offenders and terrorist offenders also tend to experience shame and rejection and have problems finding a job, a place to live, and new relationships outside their old social circles. In the UK, the current starting point for both former terrorist and sex offenders is MAPPA (multi-agency public protection arrangement): Police and the National Probation Service are acting jointly “to make arrangements for assessing and managing risks posed by sexual or violent offenders, and other persons who may cause serious harm to the public,” for example by sharing appropriate information (UK Home Office 2005, p.2). 

One expert mentioned that unlike terrorist offenders, sex offenders in the UK receive support by a local community NGO called the Circle of Trust and Accountability which provides training for people from the released offender’s local community. The goal is to build a “two-way protective cordon” which can provide a new network, long-term support for the reintegration of the released offender, and ensure his or her compliance with the requirements of the protective services. This cordon is flexible to work according to need. A similar intervention to provide closer accompaniment for the critical period after release might also be beneficial for terrorist or radicalized offenders. 



Much progress has been achieved in developing specialized risk assessment tools for violent extremism, developing approaches to managing terrorist offenders, and supporting deradicalization and rehabilitation. However, whenever a released terrorist offender commits an attack, these approaches and measures come under new scrutiny. It becomes clear that there is still a lot to be learned, improved, and communicated. Both risk assessment and management have important and lasting consequences for individuals and societies. This makes it crucial to continuously evaluate the existing approaches, conduct evidence-based research, and adapt measures accordingly. As the attacks in London or Vienna show, European countries face similar challenges and need to find effective approaches which fit their context. This paper aims to contribute to this endeavor by sharing some good practices on assessing and managing the risk of violent extremism. 



InFoEx is a joint project of the German Council on Foreign Relations (DGAP) and the Research Center for Migration, Integration and Asylum of the Federal Office for Migration and Refugees (BAMF). InFoEx brings together good practices and scientific findings from tertiary prevention of Islamist extremism in Germany and abroad. The aim of the project is to compile empirical findings on radicalization and deradicalization processes with a focus on their practical applicability for deradicalization work. To this end, the BAMF Research Centre initiated a network of research fellows who are embedded at local advice centers and research institutions, partnering with the BAMF Advice Centre on Radicalisation. Together with counselors working in these local advice centers, these research fellows represent the core members of InFoEx.


Due to the restrictions related to the COVID-19 pandemic, the workshop was organized digitally. Among the 30 participants were network partners of the BAMF Advice Centre on Radicalisation from civil society and government institutions as well as practitioners and academics from Belgium, Denmark, Germany, Netherlands, and the United Kingdom.  To align the workshop with the needs of its stakeholders, research fellows embedded at local advice centers and at research institutions in Germany shared – in agreement with practitioners at their local advice centers – specific information needs and questions regarding counseling work in tertiary prevention prior to the workshop. On these topics, external experts from research institutions, police, prison, and exit programs shared their good practices.


Bibliographic data

DGAP Report No. 3, February 4, 2021, 13 pp.

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