New Master Thesis Assignments

When citizen intervention turns into violence


Citizens are increasingly stimulated and empowered to participate in the police domain. Citizens give the police information, report crime and look out for wanted suspects. Besides, citizens also take initiative themselves to protect their neighborhood from criminals. They have started neighborhood watches, in physical form as well as via social media, or act in response to witnessing a crime in the street (e.g., detaining a shoplifter, grabbing a purse snatcher). This increase in participation can be a positive development for community safety. However, interestingly, this increase also comes with the risk that citizens take the law into their own hands and go too far in their participatory behavior. For example, they may use disproportional violence to stop an offender. Citizens taking the law into their own hands, is also called vigilantism (Haas, de Keijser, & Bruinsma, 2012). However, it is a gray area when citizens are allowed to intervene and which amount violence they are allowed to use. The use of violence has to be proportional to the crime allegedly committed, and no better (subsidiary) measures could have been taken. Since the police wants to stimulate citizens to participate, and citizens are inevitably empowered more to act upon crime, it is important to know what drives individuals to cross the line and take the law into their own hands. In this study (as part of a PhD research) we will examine how citizens make the decision to support vigilantism or are willing to become a vigilante after witnessing a crime. The focus will be on the influence of emotions (Zeelenberg, Nelissen, Breugelmans, & Pieters, 2008) as well as consequences of intervening in such situations.


The current project aims to conduct multiple lab experiments, preferably with the use of a movie in Virtual Reality glasses.


Haas, N. E., de Keijser, J. W., & Bruinsma, G. J. N. (2012). Public support for vigilantism: An experimental study. Journal of Experimental Criminology, 8(4), 387-413. doi: 10.1007/s11292-012-9144-1

Zeelenberg, M., Nelissen, R. M., Breugelmans, S. M., & Pieters, R. (2008). On emotion specificity in decision making: Why feeling is for doing. Judgment and Decision Making, 3(1), 18.


Immediately. Please contact if you are interested in this master thesis topic.