Questions that voters have always faced – how to register to vote, where to vote, and how to check in on arrival at the polling station – have taken on new urgency in today’s political climate in the U.S. Policymakers seeking to expand the vote and ensure its legitimacy are looking to research evidence to inform their decisions.

In determining voting procedures, policymakers generally seek to advance, and balance, three objectives: strong participation measured by large turnout; fair participation, whereby only eligible citizens can vote, and only vote once; and equal participation across different geographical areas and social groups. Together, these objectives safeguard the legitimacy and representativeness of the vote and ensure the public’s trust in the system. In our discussion of the studies on voting procedures, we assess whether changes in voting law advance these goals, and whether progress on one comes at the cost of another.