This thesis investigates the formation and characteristics of trust systems within communities of illicit practices operating on the dark web by using the Communities of Practice theoretical framework. The thesis aims to provide a comprehensive understanding of how these trust systems enable criminal networks on the dark web to exist and thrive while also evolving their techniques for avoiding law enforcement and adapting with takedowns. By employing a mixed-method approach that consists of a systematic literature review and qualitative interviews with experts in the field, the thesis aims to answer the question of What characterizes trust systems on the Dark Web? And how do they function to enable online communities of illicit practices?

The study identifies key themes such as mutual engagement, joint enterprise, and shared repertoire, which are crucial in understanding how trust is established and maintained in dark web communities. These themes highlight mechanisms like reputation systems, shared anonymity practices, and adaptability to disruptions. The findings offer valuable insights for law enforcement and policymakers to develop targeted interventions to disrupt these illicit networks. Moreover, the study underscores the applicability of these trust mechanisms to similar communities on the surface web, providing a broader framework for tackling online crime. As for Future research, it is necessary that researchers in the field keep tracking the subject of trust systems in the dark web as it is showing several quick shifts that are mostly instigated by law enforcement takedowns and technological advancements.