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Group violence: collective and individual issue

The out of control ‘Project X’ event in Haren, hooligans who arrange to meet up to fight and beach riots at the Hoek van Holland: group violence is increasingly hitting the headlines. Are those who took part seasoned criminals? And what characteristics do group offenders have? PhD defence on 29 September 2020.

The origins of this research project go back to 2009, PhD candidate Tom van Ham says. 'In that year riots occurred during the Veronica Sunset Grooves event held at the Hoek van Holland. Via my former employer, I was involved in a reconstruction of the riot and suspect analysis which triggered my interest in the subject. Besides this, I started out as a criminologist and neuropsychologist – disciplines where attention is also given to individual characteristics that could influence the capacity for becoming an offender.' But in academic research into collective violence, the focus is often mainly on the context in which group violence occurs.  In the dominant social identity model, it is argued that it is not individual aims and desires, but the interests and group norms within the group that determine the behaviour of people in a crowd; personal characteristics have no significant role in this theory. However, Van Ham uses the findings in this PhD dissertation to argue that individual characteristics cannot simply be ignored.

Design: Huub van Stijn

The subject is highly topical: 'There were recently confrontations in Germany between supporters of different football clubs. Demonstrations have also been getting out of hand and riots occurred in a number of Dutch cities this summer, events that are still in everyone’s mind. Media attention, the massive police response and outrage in society confirm the relevance of attention for group violence.'


The dissertation comprises four studies which became international publications. The first study examined the criminal career of a group of more than 400 group offenders before they became involved in group violence.  This random sample was comprised of people the police had arrested because of their part in group violence or people who were registered in a national database of hooligans. The second study of the dissertation considered  whether behavioural and psychological characteristics can be linked to a higher risk of becoming a repetitive offender in group violence in a period of four to five years. 'Characteristics were examined which are known to be connected to committing acts of violence: ADHD, an antisocial personality disorder, impulsiveness, sensation seeking behaviour and emotion regulation issues. The extent to which these characteristics existed in the research group in the first quantitative study was derived from police data, data from the three probation organisations and Pro Justitia reports that were drawn up by the Netherlands Institute of Forensic Psychiatry and Psychology (NIFP).'

The first two (quantitative) studies established that a small section of the group offenders (13%) can be typified as 'early high-frequency offender'. They have been involved  frequently in violent incidents in general, and serious acts of violence in particular, either alone or as part of a group. Moreover, repeat offenders of group violence – compared to non-repeat offenders – are younger at the time of the first registered offence, have a longer criminal history and suffer more often from ADHD. Thus, the studies conclude that there are several types of offenders of group violence who have various underlying reasons for their involvement in group violence.

Arranged fights

The third and fourth studies looked at whether differences exist in the contribution of contextual and individual factors when it comes to reactive and proactive forms of group violence. A case study was conducted on Project X in Haren (a spontaneous large-scale disturbance of public order), based on interviews with professionals and people present at the event and data from the 108 suspects who were arrested (criminal career and behavioural characteristics).  The fourth study – due to its clearly different nature compared to a 'spontaneous' riot – looked more closely at mutually agreed fights (arranged fights) between groups of hooligans. A comparison was made, for example, of the criminal history and behavioural characteristics of persons who were arrested at spontaneous riots. Attention was also paid to the context in which such group violence manifested itself. For example, in the Project X study a detailed reconstruction was conducted and other factors which could influence taking part in arranged fights was closely examined.

The research findings can contribute to identifying notorious offenders of group violence at an early stage.

The conclusions of the latter two studies are in line with the most important outcomes of the first two studies. The first case study established that offenders were mainly male adolescents without links to hooligan groups or who had a substantial criminal past. The build up to the riot was for a large number of those present a reason to leave. Moreover, less than 10 percent of those present actually took part in the violence. These findings imply that selection processes may have contributed to the collective violence that followed. ADHD, in particular, appeared to be a possible relevant individual characteristic of those involved. The outcomes of the second qualitative study (arranged fights) showed that the underlying norms and values of a subculture that attaches value to violent behaviour, contribute towards taking part in this kind of group violence. Offender characteristics – in particular a long and extensive criminal history – were evident among participants. As a result, the findings of this study also suggest a certain degree of 'selection'. This again implies that offender characteristics can be used to explain group violence and how people become involved in it

According to the researcher, until now  the role of individual characteristics has only been considered to a limited extent due to the belief that this would do insufficient justice to the context in which group violence manifests itself. 'When explaining group violence, attention is needed for both the mutual relationships between the 'own' and other groups such as the relevant 'mores' within specific offender groups (such as hooligans) as well as individual characteristics. So taking individual factors into consideration by no means suggests that contextual factors should be excluded completely. The research findings can contribute to identifying notorious offenders of group violence at an early stage. The findings also imply that attention for individual characteristics could provide a clearer picture of the underlying causes for a person’s involvement in group violence, the risk of reoffending and the necessary measures to prevent reoffending.

Text: Floris van den Driesche

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