PHILADELPHIA (CNN) — A Pennsylvania judge is expected to rule Tuesday on a new state law requiring every voter to present a photo ID at the polls.
Supporters argue that the law signed in March by Republican Gov. Tom Corbett will prevent voter fraud and is upheld by the Constitution.
Opponents contend that the new law will disenfranchise voters, and any implementation should be postponed until after the November 6 presidential election.
The state Supreme Court has given Commonwealth Court Judge Robert Simpson until Tuesday -- five weeks before the election -- to rule on the matter.
Simpson will determine whether people across the state have equal access to photo IDs in time for next month's election.
If not, the court is obligated to enter a preliminary injunction -- which would temporarily halt the law -- until after the election.
Prior to the new law, first-time voters in Pennsylvania were allowed to present documents such as bank statements and utility bills in lieu of photo identification. If the law is upheld, all voters will have to present a valid photo ID -- one that is sanctioned by the state -- before they cast their ballots.
To get a photo ID, residents must have a valid Social Security card; an official birth certificate or U.S. citizenship documents; and two proofs of residency, such as a utility bill or tax records.
Polls show President Barack Obama leading Republican challenger Mitt Romney in Pennsylvania, which has 20 electoral votes.
An appeal of Simpson's ruling is likely from the losing side.
Critics say the new law is an attempt by Republicans -- who overwhelmingly support the measure -- to gain the advantage in a close election.
Corbett, the governor, said the law "sets a simple and clear standard to protect the integrity of our elections."
However, lawyers on both sides admit there are no known cases of in-person voter fraud.
Civil rights organizations and attorneys filed a lawsuit in May to overturn the new law. The case made its way to the state Supreme Court, which sent the dispute back down to Simpson in the Commonwealth Court.
CNN's David Ariosto, Sarah Hoye and Deb Feyerick contributed to this report