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Providing driver’s licenses to unauthorized immigrants in California improves traffic safety

  1. Duncan Lawrencea,b,c,1
  1. aDepartment of Political Science, Stanford University, Stanford, CA 94305-6044;
  2. bImmigration Policy Lab, Stanford University, Stanford, CA 94305-6044;
  3. cImmigration Policy Lab, University of Zurich, 8050 Zurich, Switzerland;
  4. dGraduate School of Business, Stanford University, Stanford, CA 94305-6044
  1. Edited by Mary C. Waters, Harvard University, Cambridge, MA, and approved March 3, 2017 (received for review November 17, 2016)


Several states have experimented with more inclusive policies toward immigrants. There is little empirical evidence related to their impact. Our study examines the short-term traffic safety effects of one of the largest-scale state policies focused on the integration of unauthorized immigrants: California’s extension of driving privileges to unauthorized immigrants. We find that this policy did not increase the total number of accidents or the occurrence of fatal accidents, but it did reduce the likelihood of hit and run accidents, thereby improving traffic safety and reducing costs for California drivers. Our findings have important implications for policymakers: providing unauthorized immigrants with access to driver’s licenses can create positive externalities for the communities in which they live.


The integration of immigrants presents a major challenge for policymakers in the United States. In an effort to improve integration, several US states recently have implemented laws that provide driver’s licenses to unauthorized immigrants. These new laws have sparked widespread debate, but we lack evidence on the traffic safety impact of these policies. We examine the short-term effects of the largest-scale policy shift, California’s Assembly Bill 60 (AB60), under which more than 600,000 licenses were issued in the first year of implementation in 2015 alone. We find that, contrary to concerns voiced by opponents of the law, AB60 has had no discernible short-term effect on the number of accidents. The law primarily allowed existing unlicensed drivers to legalize their driving. We also find that, although AB60 had no effect on the rate of fatal accidents, it did decrease the rate of hit and run accidents, suggesting that the policy reduced fears of deportation and vehicle impoundment. Hit and run behaviors often delay emergency assistance, increase insurance premiums, and leave victims with significant out of pocket expenses. Overall, the results suggest that AB60 provides an example of how states can facilitate the integration of immigrants while creating positive externalities for the communities in which they live.


  • ?1H.L., J.H., and D.L. contributed equally to this work.

  • ?2To whom correspondence should be addressed. Email: jhain{at}stanford.edu.

Freely available online through the PNAS open access option.

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