Associate Professor

Jan-Willem van Prooijen

Associate Professor

Phone: +31 (0)20 5988851
Room: MF-B558

Personal webpage


I work on three interrelated research projects: Social injustice, belief in conspiracy theories, and political ideology. In my research on social injustice, I examine the general, overarching question of how people cope with situations that they consider to be unfair. I address this question from three complementary perspectives. The first perspective is when people themselves feel unfairly treated, focusing specifically on procedural justice (i.e., the extent to which people evaluate the decision-making procedures that leaders use as fair). The second perspective is when people perceive injustice as observers, focusing on punishment sentiments, fairness-based responses to crime victims, and intervention behavior (e.g., the bystander effect). The third perspective is when people are perpetrators of injustice, focusing specifically on corruption. For this latter perspective I collaborate with a NWO funded PhD student (Nils Kobis).

My work on belief in conspiracy theories addresses the question which psychological factors predict if, and in what situations, people are likely to believe that threats to the social order are caused by an evil conspiracy of societal power holders. Large portions of the population believe in conspiracy theories about specific events (e.g., the 9/11 terrorist strikes; the death of Princess Diana) or about ongoing crises (e.g., climate change; economic crises). What specific sense-making processes facilitate such belief in conspiracy theories? How do feelings of uncertainty relate to such beliefs? To what extent do conspiracy beliefs reflect a genuine concern for the collective interest? What are the societal and political implications of belief in conspiracy theories? This project was awarded a NWO conflict & Security grant in 2010.

Finally, recently my work expanded to broader issues in political psychology with research on political ideology. My main focus in this project is on political extremism. How do the political extremes differ from moderates? In what ways does the (extreme) left differ from the (extreme) right, and in what ways are they similar? Are both extremes driven by uncertainty and fear—and if so, why then are the political extremes typically rather confident of their views? Is prejudice and outgroup derogation specific to the political right, as some theories assert, or do these phenomena occur among both extremes?


I received my PhD from the department of Social and Organizational Psychology at Leiden University in 2002. During my PhD studentship I already moved to  VU University Amsterdam, where I currently work as an Associate Professor at the Department of Experimental and Applied Psychology . Since 2011, I also work one day a week as a Senior Researcher at the Netherlands Institute for the Study of Crime and Law Enforcement (NSCR). I teach introduction to Social Psychology in the first bachelor year, am teaching coordinator for the social psychology program, and coordinate the Research Master in Social Psychology.

Research interests

My research interests are described elaborately under “Projects”. My research focuses on social injustice, belief in conspiracy theories, and political ideology, broadly defined. To study these topics I utilize both experimental and applied research methods. I take an interdisciplinary approach to these issues, with social psychology as main field of expertise, but with close collaborative connections to fields such as organizational psychology, criminology, and political science.


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Recent publications

J Van Bavel & P Boggio (2020) National identity predicts public health support during a global pandemic.
G Spadaro, K Gangl, JW Van Prooijen, PAM Van Lange & CO Mosso (2020) Enhancing feelings of security: How institutional trust promotes interpersonal trust. PloS one 15 (9), e0237934
JW van Prooijen & M Song (2020) The cultural dimension of intergroup conspiracy theories. British Journal of Psychology
C Federico (2020) When do psychological differences predict political differences? Engagement and the psychological bases of political polarization. PsyArXiv
JW van Prooijen & SMHC Kuijper (2020) A comparison of extreme religious and political ideologies: Similar worldviews but different grievances. Personality and Individual Differences 159, 109888
S Altaf, MZ Iqbal, JW van Prooijen & M Ikramullah (2020) The mechanism behind employee agreeableness and group performance ratings: a Pakistani study. International Journal of Productivity and Performance Management
I Van Sintemaartensdijk, JL Van Gelder, JW Van Prooijen, C Nee, M Otte & ... (2020) Mere presence of informal guardians deters burglars: a virtual reality study. Journal of Experimental Criminology, 1-20
P Strelan, JW Van Prooijen & M Gollwitzer (2020) When transgressors intend to cause harm: The empowering effects of revenge and forgiveness on victim well‐being. British journal of social psychology 59 (2), 447-469
JW Van Prooijen & APM Krouwel (2020) Overclaiming knowledge predicts anti-establishment voting. Social Psychological and Personality Science 11 (3), 356-363
M Zwicker, JW van Prooijen & A Krouwel (2020) Persistent Beliefs: Political Extremism Predicts Ideological Stability over Time. Group Processes and Intergroup Relations
Y Kutiyski, A Krouwel & JW van Prooijen (2020) Political extremism and distrust: Does radical political orientation predict political distrust and negative attitudes towards European integration?. The Social Science Journal, 1-16
K Fousiani & JW van Prooijen (2020) Punishment Reactions to Powerful Suspects: Comparing a “Corrupt” versus a “Leniency” Approach of Power.
V Ljujic, I Versteegt, F Weerman, F Thijs, JW van Prooijen, F el Bouk & ... (2020) Testing a Threat Model of Terrorism: A multi-method study about socio-economic and psychological influences on terrorism involvement in the Netherlands. Understanding Recruitment to Organized Crime and Terrorism, 147-171
JW Van Prooijen, O Klein, J Milosevic Dordevic, P Knight & M Butter (2020) Social-Cognitive Processes underlying belief in conspiracy theories. Routledge Handbook of Conspiracy Theories, 1, 168-180
RJM Neve, FM Weerman, S Eris & JW van Prooijen (2020) Radicalisation and travelling to Syria among delinquent youths: A case study from the Netherlands. Journal for Deradicalization, 249-286
JW van Prooijen (2019) An existential threat model of conspiracy theories.. European Psychologist
FM Weerman & JW Prooijen (2019) Radicalisering in problematische jeugdgroepen.
R Neve, S Eris, F Weerman, JW Prooijen, V Ljujic & I Versteegt (2019) Radicalisering in problematische jeugdgroepen.
K Fousiani & JW van Prooijen (2019) Reactions to offenders: Psychological differences between beliefs versus punishment. British Journal of Social Psychology 58 (4), 894-916
M Dong, JW van Prooijen & PAM van Lange (2019) Self-enhancement in moral hypocrisy: Moral superiority and moral identity are about better appearances. PloS one 14 (7), e0219382

View full list of publications on Google Scholar