Some states require voters at a polling place to produce photographic identification (photo ID) before casting a ballot. Such requirements have emerged as a controversial issue in the 2012 presidential election, and they are the focus of this report. Since 2008, almost half the states have enacted laws, many in 2012, relating to voter identification, with several containing photo ID requirements. In contrast, while several bills with voter identification provisions have been introduced in the 112th Congress, none have received committee or floor consideration. About 30 states require voters to provide some form of identification when voting in person, although few require such documentation for absentee voters. Seven of these states require a photo ID for polling-place voting but permit alternatives such as signing an affidavit for voters without an ID. With respect to what type of photo ID is acceptable and what happens if a voter does not have it, no two states are the same. Four states-Georgia, Indiana, Kansas, and Tennessee-permit only voters who present a photo ID to cast a ballot, with few exceptions. Pennsylvania, South Carolina, Texas, and Wisconsin recently enacted similarly strict photo ID requirements that are not in effect at present because of court or U.S. Department of Justice (DOJ) actions. In 2008, the U.S. Supreme Court upheld the Indiana voter photo ID law under the U.S. Constitution on equal protection grounds. However, in more recent cases, the question being considered is whether such laws violate relevant state constitutions. Whether voter photo ID laws comport with the Voting Rights Act (VRA) has also recently been considered by the courts and DOJ. Section 5 of the VRA requires certain states and jurisdictions to obtain preclearance from either DOJ or the U.S. District Court for the District of Columbia before implementing a change to any voting practice or procedure. For example, in March 2012, DOJ denied preclearance approval under Section 5 to laws in Texas and South Carolina that require voters to show photo ID prior to casting a ballot. Subsequently, federal courts also denied preclearance to both laws, so they will not be in effect for the November 6, 2012, election. The South Carolina law, however, was granted preclearance to take effect in any election beginning in 2013. Photo ID requirements enacted in Alabama and Mississippi are slated for implementation after 2012, and are also subject to preclearance. Supporters of photo ID requirements emphasize the need to prevent voter fraud, while opponents emphasize the need to avoid disenfranchising legitimate voters who do not have ready access to a photo ID. Polling data suggest that most voters and most local election officials support a photo ID requirement but that many are also concerned about the risk of disenfranchisement. The policy controversy centers largely on whether the risk of disenfranchisement or the risk of voter fraud is the greater threat to the integrity of the electoral process. This policy debate is being conducted in the absence of a broad consensus about the evidence pertaining to those risks. Election administration is complex, and changes in photo ID requirements may affect other aspects as well, among them the use of provisional ballots, the potential for long lines, and the possibility that poll workers could misapply the new rules. It may be advantageous to have as much time as possible to implement changes to voting procedures, so that election officials, poll workers, and voters have time to adjust.