In recent years, many European countries have taken far-reaching measures to combat the criminal activities of outlaw motorcycle gangs (OMCGs). Meanwhile, empirical research into the ways OMCGs are involved in and influence the crimes of their members is largely lacking. This study presents the main findings of research based on police files of cases that were filed against members of Dutch OMCGs. We apply a criminological scenario approach to analyse to what extent and in which ways OMCGs are involved in the crimes of their members. The results show that OMCG membership particularly plays an indirect role in the criminal behaviour of OMCG members. Board members, for example, give permission for criminal acts, regulate mutual relationships between members, non-members and rival OMCGs during conflict situations, and forbid (criminal) behaviour of members that is harmful to the OMCG. OMCGs function as a pool of co-offenders and as a market for criminal enterprises. Members also use the violent reputation of OMCGs in specific criminal activities. OMCGs are less frequently directly involved in crimes. Direct involvement of OMCGs is most apparent in organized inter-gang violence and violence against their own members.

近年来，许多欧洲国家采取了影响深远的措施来打击非法摩托车团伙（OMCG）的犯罪活动。同时，关于OMCG参与和影响其成员犯罪的方式的实证研究非常缺乏。这项研究基于对荷兰OMCG成员提起的案件的警察档案，提出了研究的主要发现。我们使用犯罪学情景方法来分析OMCG在多大程度上以何种方式参与其成员的犯罪。结果表明，OMCG成员在OMCG成员的犯罪行为中尤其起间接作用。例如，董事会成员在冲突情况下允许犯罪行为，规范成员，非成员和相互竞争的OMCG之间的相互关系，并禁止对OMCG有害的成员（犯罪）行为。OMCG作为共同犯罪者的集合和犯罪企业的市场。会员还在特定犯罪活动中使用OMCG的暴力名声。OMCG很少直接参与犯罪。OMCG的直接参与在有组织的帮派间暴力和针对其成员的暴力中最为明显。