By Caroline Logan, Randy Borum, and Paul Gill

Violent extremism has galvanized public fear and attention. Driven by their concerns, the public has pushed for law enforcement and mental health systems to prevent attacks rather than just respond to them after they occur. The prevention process requires guidance for practitioners and policymakers on how best to identify people who may be at risk, to understand and assess the nature and function of the harm they may cause, and to manage them to mitigate or prevent harm. Violent Extremism provides such guidance.

Over 10 chapters, prepared by leading experts, this handbook illuminates the nature of violent extremism and the evolution of prevention-driven practice. Authors draw on the literature and their experience to explain which factors might increase (risk factors) or decrease (protective factors) risk, how those factors might operate, and how practitioners can prepare risk formulations and scenario plans that inform risk management strategies to prevent violent extremist harm.

Each chapter is crafted to support thoughtful, evidence-based practice that is transparent, accountable and ultimately defensible. Written for an international audience, the volume will be of interest to law enforcement and mental health professionals, criminal justice and security personnel, as well as criminologists, policymakers and researchers.

London, UCL Press. 2023, 319pg

By Michelle Sydes, Lorelei Hine, Angela Higginson, James McEwan, Laura Dugan, Lorraine Mazerolle

Background: Criminal justice agencies are well positioned to help prevent the radicalisation of individuals and groups, stop those radicalised from engaging in violence, and reduce the likelihood of terrorist attacks. This Evidence and Gap Map

(EGM) presents the existing evidence and gaps in the evaluation research. Objectives: To identify the existing evidence that considers the effectiveness of criminal justice interventions in preventing radicalisation, violent extremism and terrorism.

Search Methods: We conducted a comprehensive search of the academic and grey literature to locate relevant studies for the EGM. Our search locations included the Global Policing Database (GPD), eight electronic platforms encompassing over 20 academic databases, five trial registries and over 30 government and nongovernment websites. The systematic search was carried out between 8 June 2022 and 1 August 2022.

Selection Criteria: We captured criminal justice interventions published between January 2002 and December 2021 that aimed to prevent radicalisation, violent extremism, and/or terrorism. Criminal justice agencies were broadly defined to include police, courts, and corrections (both custodial and community). Eligible populations included criminal justice practitioners, places, communities or family members, victims, or individuals/groups who are radicalised or at risk of becoming radicalised. Our map includes systematic reviews, randomised controlled trials, and strong quasi‐experimental studies. We placed no limits on study outcomes, language, or geographic location.

Data Collection and Analysis: Our screening approach differed slightly for the different sources, but all documents were assessed in the systematic review software program DistillerSR on the same final eligibility criteria. Once included, we extracted information from studies using a standardised form that allowed us to collect key data for our EGM. Eligible systematic reviews were assessed for risk of bias using the AMSTAR 2 critical appraisal tool.

United States, Campbell Collaboration. 2023, 53pg