A Pennsylvania appellate judge ruled Friday that a law requiring voters to show photo identification at the polls is unconstitutional.

Judge Bernard McGinley of the Commonwealth Court ruled that a revision to the state’s election code commonly called the “voter ID law” threatened “the franchise of hundreds of thousands of registered electors.” Several public-interest groups jointly filed a challenge against Gov. Tom Corbett and Secretary of the Commonwealth Carol Aichele in May 2012, only two months after the Pennsylvania General Assembly approved the bill.

The ruling reflects a nationwide trend, coming at a time when both Texas and North Carolina are facing scrutiny over their own similarly restrictive and currently active voter ID laws. 

Under the law, introduced in early 2012 by Republican Pennsylvania Rep. Daryl Metcalfe, voters were required to present accepted forms of ID — such as state and U.S. government-issued driver’s licenses or photo IDs and IDs issued by universities and colleges in the state — at the polls to vote. The previous law required voters to show ID when they voted for the first time in an election district, but allowed them to present non-photo forms of identification after the first time.

While Republicans who pushed for the law argued it would reduce voter fraud, critics said the law would disenfranchise poorer residents. The critics, including Democratic lawmakers and civil rights advocates, argued that it unfairly targeted certain groups of voters who were less likely to hold state driver’s licenses or other approved IDs. These groups included young voters, the elderly and the poor, among others.

During hearings held as part of the appeal related to the challenge last July, Bernard Siskin, a statistician, gave testimony that more than half a million eligible Pennsylvanian voters did not have any of the forms of ID allowed under the law. Diana Mutz, a political science professor at the University of Pennsylvania, said during the hearings that although the state government conducted a campaign to educate voters about the law, it failed to correctly inform voters about the requirements of the law.

McGinley sided with the groups that filed the suit, which included the American Civil Liberties Union of Pennsylvania, the Public Interest Law Center of Philadelphia, the National Association for the Advancement of Colored People and several other advocacy groups.

“The right to vote, fundamental in Pennsylvania, is irreplaceable, necessitating its protection before any deprivation occurs,” McGinley wrote in his decision.

Although the Republican-controlled state legislature passed the law before the 2012 presidential election, a commonwealth judge said poll workers could not prevent those without approved IDs from casting ballots.

Reactions to the ruling have been split along party lines.

Pratt Wiley, the director of voter protection for the Democratic National Committee, said the ruling would protect voters from disenfranchisement.

“This law should never have been enacted, and Democrats remain committed both to electing individuals who support expanding access to the voting booth and to supporting efforts to reverse burdensome voting laws like this one across the country,” Wiley said in a statement the Democratic Party issued after the ruling.

Rep. Dan Frankel, D-Squirrel Hill, called the ruling a “victory for Pennsylvanians” in a statement.

Rob Gleason, the chairman of the Republican Party of Pennsylvania, said in a statement that he was disappointed with the ruling.

“The overwhelming majority of Pennsylvanians support a way to protect their right to vote and combat voter fraud,” Gleason said.

Rep. Daryl Metcalfe, who introduced the bill in 2011, was unavailable for comment Friday afternoon.

Although McGinley declared the law unconstitutional, the state’s attorneys may still appeal the case to the state’s Supreme Court.

“We continue to evaluate the opinion and will shortly determine whether post-trial motions are appropriate,” James Schultz, an attorney for Corbett, said in a statement the governor’s office released after the ruling.