The Effect of Voter Identification Laws on Turnout
Since the passage of the "Help America Vote Act" in 2002, nearly half of the states have adopted a variety of new identification requirements for voter registration and participation by the 2006 general election. There has been little analysis of whether these requirements reduce voter participation, especially among certain classes of voters. In this paper we document the effect of voter identification requirements on registered voters as they were imposed in states in the 2000 and 2004 presidential elections, and in the 2002 and 2006 midterm elections. Looking first at trends in the aggregate data, we find no evidence that voter identification requirements reduce participation. Using individual-level data from the Current Population Survey across these elections, however, we find that the strictest forms of voter identification requirements—combination requirements of presenting an identification card and positively matching one's signature with a signature either on file or on the identification card, as well as requirements to show picture identification—have a negative impact on the participation of registered voters relative to the weakest requirement, stating one's name. We also find find evidence that the stricter voter identification requirements depress turnout to a greater extent for less educated and lower income populations, for both minorities and non-minorities.
Additional InformationAlso known as VTP Working Paper #57. This paper replaces an earlier version with the same title that was distributed October, 2007. Previous versions of this paper were presented at the 2007 Summer Methods Meeting, The Society for Political Methodology, Pennsylvania State University; the 2007 Annual Meeting of the American Political Science Association, Chicago, Illinois; and at the Second Annual Conference on Empirical Legal Studies, New York University Law School. We thank Shigeo Hirano, Thad Hall, and Andrew Martin who provided comments at each conference respectively, as well as conference participants. We also thank Clark Benson, Andrew Gelman, Sam Hirsch, and Nate Persily for helpful comments and conversations. We thank the Carnegie Corporation of New York and the John S. and James L. Knight Foundation for their support of our research through grants to the Caltech/MIT Voting Technology Project. The analysis presented here, and the interpretations of our analysis, are those of the authors and not of the Caltech/MIT Voting Technology Project, nor the foundations supporting this research. Please note that Katz has served as an expert witness in two lawsuits involving voter identification requirements, however the research presented here was neither funded by any interested party to those lawsuits nor discussed in court testimony.
Submitted - SSRN-id1084598.pdf
Submitted - sswp1267_-_revised.pdf