The law, known as Act 18, requires all voters to present specific types of photo identification at the polls. If they do not have the correct ID, the law says, voters can cast a provisional ballot, and will then have six days to present one of the required forms of ID, such as a valid driver's license, to election officials.
Simpson said he was considering halting only the provisional-ballot requirements. Under the scenario he said he was considering, voters without appropriate photo ID could vote provisionally, but would no longer have to produce identification within six days, as their votes would be counted.
Attorneys for the plaintiffs, which include civil-rights and other civic groups, argued in legal briefs Friday that such a limited injunction would set the stage for voter disenfranchisement. That outcome, they said, would go against what the state Supreme Court directed Simpson to do: enjoin the law if he believes any disenfranchisement will occur.
"This approach," the plaintiffs' attorneys wrote, "in effect would create a bifurcated system where voters with photo ID vote by regular ballot, while voters without photo ID vote by provisional ballot and are subject to all of the preexisting rules governing provisional ballots."
Those rules require that provisional ballots be counted not on Election Day but at a later date, at which point they could be subject to challenges from political parties and ultimately not be counted.
"Under these circumstances, the commonwealth cannot provide any assurance that every provisional ballot cast by a voter who lacks photo ID will be counted," they contended.
Attorneys for Gov. Corbett's administration countered in their legal briefs that plaintiffs' witnesses who testified in this week's hearings were either frustrated with the process of getting an ID, or had run into trouble getting identification because they were not yet registered to vote or because their names did not appear on the state's registration rolls.
They noted that an injunction must only address "unlawful activity," and that a court must take care not to drag lawful activity under that umbrella. They pointed out that other courts have said requiring a voter to present photo identification is lawful.
"Any legitimate concern about voter disenfranchisement, if it merits an injunction at all, could be narrowly tailored to any threat that votes will not be counted in this election," the lawyers wrote.
Whatever Simpson's decision, it is widely expected that it will be appealed back to the high court.
Contact Angela Couloumbis at 717-787-5934 or firstname.lastname@example.org, or follow on Twitter @AngelasInk.