This morning, in a victory for election integrity, a Pennsylvania district court judge denied a preliminary injunction to stop Pennsylvania’s new voter ID law from going into effect.

The law, passed in March 2012, minimally changes Pennsylvania’s election code to require citizens voting in person on Election Day to present photo identification. Acceptable forms of photo identification include IDs issued by the federal or state government, such as municipalities, accredited public or private schools, and care facilities. Citizens who cannot produce an approved form of ID may still cast a provisional ballot provided that the person delivers proof of identification within six days after the election. The law imposes a similar ID requirement for absentee ballots.

Pennsylvania’s Department of Transportation is charged with issuing free identification cards. For those who cannot afford the minimal cost of supporting documentation, such as a birth certificate, their votes will still count if they sign an affirmation that they can’t afford the cost.

The challengers claimed that many citizens will be disenfranchised or severely burdened by the photo ID requirement. At a trial in July, the challengers put forth testimony regarding the number of registered voters supposedly without certain types of photo ID (e.g., drivers licenses) as of June 2012, but others have noted that most of these voters have other approved IDs that they use to pass through airport security or get into government buildings.

Judge Robert Simpson flatly rejected the challengers’ attempt to “inflate the numbers” of disenfranchised voters—which he estimated were “somewhat more than 1% and significantly less than 9%,” as claimed by the petitioners. He also found that the testimony of the petitioners’ expert was “not credible” and demonstrated bias.

This outcome is similar to those in the unsuccessful lawsuits against the voter ID laws of Georgia and Indiana. In all three states, the courts threw out the opinions of the alleged experts hired by the plaintiffs as “not credible.”

In a motion for a preliminary injunction, the challengers must demonstrate their likely success on the merits. The challengers failed to convince the judge that Pennsylvania’s law is facially unconstitutional (rather than as applied, which means that the law is unconstitutional only in its application to a particular person under particular circumstances). The challengers provided “speculation about hypothetical or imaginary cases,” which Judge Simpson correctly observed has “no place in a facial challenge.”

Fraud in elections is a legitimate problem, and states from Colorado to Rhode Island have addressed it by passing laws that require identification at the polls. Voter ID laws strengthen enfranchisement of registered voters and ensure the integrity of elections, and now Pennsylvania joins the ranks of other states with common-sense voter ID laws that have withstood judicial scrutiny, such as Indiana, Arizona, and Georgia.