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Police demilitarization and violent crime


Policymakers and advocates make contradictory claims about the effects of providing military equipment to local law enforcement, but this intervention is not well understood because of severe data limitations and inferential challenges. I use 3.8 million archived inventory records to estimate the magnitude of sources of bias in existing studies of the 1033 Program. I show that most variation in militarization comes from previously unobserved sources, which implies that studies that show crime-reduction benefits are unreliable. I then leverage recent policy changes to evaluate the effect of military equipment: the Obama Administration recalled property under Executive Order 13688, which resulted in a forced demilitarization of several hundred departments. Difference-in-difference estimates of agencies that retained similar equipment show negligible or undetectable impacts on violent crime or officer safety. These findings do not suggest that similar scale federal reforms designed to demilitarize police would have the downside risks proposed by proponents of military transfers.

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Fig. 1: Roughly one in five controlled weapons turn over within 4 years.
Fig. 2: Demilitarization did not lead to substantively significant increases or decreases in violent crime or officer safety.
Fig. 3: EO 13688 achieved near-perfect compliance and resulted in demilitarization among affected LEAs.
Fig. 4: Local LEAs with recalled equipment were concentrated in the South, Midwest, and California.

Data availability

The data supporting the findings reported in this study, along with the underlying 1033 Program inventory records, have been deposited in the Harvard Dataverse and can be found at

Code availability

Replication code for the findings reported in this study has been deposited in the Harvard Dataverse and can be found at:


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The author received no specific funding for this work. The author thanks K. Crabtree, C. Davenport, J. Mummolo, J. Rogowski, B. Schneer, M. Sen, Y. Shiraito, S. Streeter, Y. Zhukov and seminar audiences at the University of Michigan and Harvard University for comments and suggestions. J. Beckman, A. Eldes, J. Fortney, S. Patel, B. Vomastek and J. Walden provided helpful research assistance.

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K.L. designed and performed the research, analysed the data and wrote the paper.

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Correspondence to Kenneth Lowande.

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Lowande, K. Police demilitarization and violent crime. Nat Hum Behav 5, 205–211 (2021).

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