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Establishing the Rule of Law in Weak and War-torn States: Evidence from a Field Experiment with the Liberian National Police



How to restore citizens’ trust and cooperation with the police in the wake of civil war? We report results from an experimental evaluation of the Liberian National Police’s (LNP) “Confidence Patrols” program, which deployed teams of newly retrained, better-equipped police officers on recurring patrols to rural communities across three Liberian counties over a period of 14 months. We find that the program increased knowledge of the police and Liberian law, enhanced security of property rights, and reduced the incidence of some types of crime, notably simple assault and domestic violence. The program did not, however, improve trust in the police, courts, or government more generally. We also observe higher rates of crime reporting in treatment communities, concentrated almost entirely among those who were disadvantaged under prevailing customary mechanisms of dispute resolution. We consider implications of these findings for post-conflict policing in Liberia and weak and war-torn states more generally.


Corresponding author

*Robert A. Blair, Assistant Professor, Department of Political Science and Watson Institute for International and Public Affairs, Brown University,
Sabrina M. Karim, Assistant Professor, Department of Government, Cornell University,
Benjamin S. Morse, PhD Candidate, Department of Political Science, Massachusetts Institute of Technology,


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This research was supported by the International Growth Center and the Folke Bernadotte Academy. For helpful comments, we thank participants at the “New Perspectives on the State, Violence and Social Control” conference at the University of Chicago, the Evidence in Governance and Politics (EGAP) 19 conference, the International Development Seminar at the College of William & Mary, the International Political Economy Seminar at Johns Hopkins University (SAIS), the Joint Degree Program in Social Policy Seminar at Princeton University, the Yale Institute for Social and Policy Studies (ISPS) Experiments Workshop, the Boston-Area Working Group in African Political Economy (B-WGAPE), the Applied Micro Economics Seminar at Brown University, and three anonymous reviewers. Prince Williams provided superb research assistance. We are also indebted to the leadership of the Liberian National Police for their partnership with us. Replication files are available at the American Political Science Review Dataverse:



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Establishing the Rule of Law in Weak and War-torn States: Evidence from a Field Experiment with the Liberian National Police



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