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Differences between lone, pair and group terror attackers analysed in study

Analysis of more than 140 individuals convicted of extremist offences in England and Wales has revealed how terrorists who act alone, in pairs, or in a group differ in background, social influence and activity.

    Police officer standing with his back to police tape with police cars in the distance
    Whether the attack progressed or failed was also analysed in the research

    The study of specialist files was carried out by Nottingham Trent University (NTU), His Majesty’s Prison and Probation Service (HMPPS) and Bournemouth University and builds on a previous report into internet radicalisation, which was the first to use closed source data of this kind of analysis.

    It aims to identify the risk posed by each of these sub-groups based on in-depth professional risk assessments rather than the severity of their offence, as previously inferred.

    In total, 44 lone actors, 20 lone pairs and 79 group actors were identified in the sample. Both lone and group actors were typically male (over 90%) with the figure lower for lone pairs (75%). The average age for all perpetrators at sentencing was under 30 and the majority were born in the UK. Over time, lone-actor attacks have become increasingly prominent, whilst the opposite is true for group attacks.

    Findings showed that attackers affiliated with the Extreme Right Wing were more likely to commit attacks alone or in pairs, in contrast to Islamist extremists who were more likely to attack as a group.

    Jens Binder
    Associate Professor Jens Binder, School of Social Sciences

    The internet was also found to play an important role in radicalisation pathways and attack preparation for lone actors and lone pairs, but a lesser role for group-based attackers. Lone-attackers were more likely to signal their intent online, which may make it easier to detect them and to counter attacks at an earlier stage.

    Whether the attack progressed or failed was also analysed in the research, showing that lone actors were least effective. While 30% of lone attackers completed their plan, this was the case for 40% of lone pairs and 41% of group actors. Across all three groups the majority of plots were thwarted by police and security services.

    In addition, the study investigated prevalence of mental health issues and found that these were highest among lone actors and lone pairs. Using a wider definition of mental health, lone terrorists were the most likely to have mental illness, neurodivergence or a personality disorder based on percentages - at 57% of cases compared to 45% of lone pairs and 10% of group actors respectively.

    Dr Jonathan Kenyon, lead author of the study and working for HMPPS Counter Terrorism – Assessment and Rehabilitation Centre, said: “One way of protecting the public more effectively against terrorist violence is to develop insight to support identification of potential attackers and evaluate risk more effectively.

    “The high prevalence of a range of mental health issues suggests that we need more preventative responses to deter would-be attackers from their path. For example, particular attention should be paid to those with mental health concerns who are expressing support for extreme views, especially those supporting an Extreme Right Wing ideology.”

    Dr Jens Binder, Associate Professor of Psychology at NTU’s School of Social Sciences, said: “This study gives us an increased understanding of different attacker profiles, which can help guide counter-terrorism approaches and future policy. In particular, our analysis shows that online activity is no longer an effective shield against detection.”

    The research An Analysis of Terrorist Attack Perpetrators in England and Wales: Comparing Lone Actors, Lone Dyads and Group Actors has been published in the Journal of Threat Assessment and Management.

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      About Nottingham Trent University

      Nottingham Trent University (NTU) received the Queen’s Anniversary Prize for Higher and Further Education in 2021 for cultural heritage science research. It is the second time that NTU has been bestowed the honour of receiving a Queen’s Anniversary Prize for its research, the first being in 2015 for leading-edge research on the safety and security of global citizens.

      The Research Excellence Framework (2021) classed 83% of NTU’s research activity as either world-leading or internationally excellent. 86% of NTU’s research impact was assessed to be either world-leading or internationally excellent.

      NTU was awarded The Times and The Sunday Times Modern University of the Year 2023 and ranked University of the Year in the Whatuni Student Choice Awards 2023. It was awarded Outstanding Support for Students 2020 (Times Higher Education Awards), University of the Year 2019 (Guardian University Awards, UK Social Mobility Awards), Modern University of the Year 2018 (Times and Sunday Times Good University Guide) and University of the Year 2017 (Times Higher Education Awards).

      NTU is the 5th largest UK institution by student numbers, with approximately 40,000 students and more than 4,400 staff located across five campuses. It has an international student population of 7,000 and an NTU community representing over 160 countries.

      Since 2000, NTU has invested £570 million in tools, technology, buildings and facilities.

      NTU is in the UK’s top 10 for number of applications and ranked first for accepted offers (2021 UCAS UG acceptance data). It is also among the UK’s top five recruiters of students from disadvantaged backgrounds and was the first UK university to sign the Social Mobility Pledge.

      NTU is ranked the second most sustainable university in the world in the 2022 UI Green Metric University World Rankings (out of more than 900 participating universities).

    Published on 18 January 2024
    • Category: Press office; Research; School of Social Sciences