In Crawford v. Marion County Election Board, 128 S. Ct. 1610 (2008), the U.S. Supreme Court upheld an Indiana law requiring government-issued photo identification prior to voting. The Court held that “[t]he application of the statute to the vast majority of Indiana voters is amply justified by the valid interest in protecting the integrity and reliability of the electoral process.”

The Court held that Indiana has a legitimate justification in deterring and detecting voter fraud: “The State has a valid interest in participating in a nationwide effort to improve and modernize election procedures that have been criticized as antiquated and inefficient.” The Court recounted problems of voter fraud, including a humorous example from the era of Boss Tweed in the New York City elections of 1868: "When you've voted 'em with their whiskers on, you take 'em to a barber and scrape off the chin fringe. Then you vote 'em again with the side lilacs and a mustache. Then to a barber again, off comes the sides and you vote 'em a third time with the mustache. If that ain't enough and the box can stand a few more ballots, clean off the mustache and vote 'em plain face. That makes every one of 'em good for four votes." A. Callow, The Tweed Ring 210 (1966) (quoting M. Werner, Tammany Hall 439 (1928)).

The Court denied the Democrats’ facial challenge to the Indiana law. A “facial challenge” is one based on the terms of a law without any proof of its being applied in an unconstitutional manner. This photo ID law has been in effect in Indiana since July 1, 2005, and Georgia also has a photo ID requirement for voting.

Indiana never provided any evidence of voter impersonation, but the Court said that it did not have to. Rather, the mere risk of voter impersonation, which is undeniable in light of proven patterns of voter fraud like that described above, was enough justification to uphold the photo ID law. Under this rationale, any state in the country may pass a law like Indiana's and expect it to be upheld under a similar challenge.

Prior to the Court’s ruling, some observers (such as Linda Greenhouse of the New York Times) were critical of the Democrats for appealing this case to the Supreme Court. It seemed clear that the High Court would uphold this law, and thereby set a new precedent nationwide inviting similar laws. States within the Ninth Circuit, which would not be so receptive to these laws because they probably impact more Democratic voters than Republican voters, can now immediately copy what Indiana has done even though their appellate court may have disallowed it. Arizona, a hotbed of illegal aliens, can now enact a photo ID voter law just like Indiana’s.

The Court, in affirming this law, noted that the Democrats were unable to quantify the amount of any burden placed by it on voters. The Democrats had not proven their case, but appealed to the Supreme Court to strike down the Indiana law anyway. That approach may have worked a decade ago, when the make-up of the Court was different, but it does not work today. Increasingly, the Court has emphasized its unwillingness to overstep its power by invalidating laws based on facial challenges without specific evidence of unconstitutional applications of the laws.

Justice John Paul Stevens, who typically sides with the liberal wing of the Court, surprised many by taking the lead in favor of the Indiana law and writing the plurality opinion, joined by Chief Justice John Roberts and Justice Anthony Kennedy. Justice Antonin Scalia wrote a broader opinion affirming the law because it applied to all voters equally, and he was joined by Justices Clarence Thomas and Samuel Alito. Justices David Souter, Ruth Bader Ginsburg and Stephen Breyer dissented.