Republican leaders who backed the law say that it is simply intended to thwart voter fraud.
Attorney David Gersch, who is appealing Simpson's ruling, said Thursday that the state can't cite any examples of people who were investigated for or convicted of voter fraud. Gersch also noted that thousands of residents don't have easy access to PennDOT locations to get the voter IDs.
John Knorr, the commonwealth's attorney, said that newspapers have exaggerated the number of people who won't have state ID by the election. The burden on residents to get ID, he said, was "minimal."
Justices Seamus McCaffery and Debra McCloskey Todd, both Democrats, wondered aloud why the law couldn't be implemented over several years, instead of just before the election.
Justice Michael Eakin, a Republican, underscored the value of the law, noting that fraud has existed since George Washington.
So . . . now what?
* Voter ID is probably here to stay. The justices, who are split evenly - three Democrats, three Republicans - are expected to issue a ruling soon.
"I'm inclined to think it's an uphill climb to get an injunction," said Temple University law professor Mark Rahdert. "Once a lower court rules against the challengers, it sets all the machinery of justice against getting that decision overturned."
Zack Stalberg, president of the good-government group the Committee of Seventy, said that Simpson's ruling, coupled with the Supreme Court's even political split, "adds up to there being a good chance that it will be upheld."
Unless, of course . . .
* Something unexpected happens. "We have turned back similar laws in multiple states across this country . . . from Wisconsin to Minnesota to North Carolina to Texas," NAACP President Benjamin Todd Jealous said after Thursday's hearing. "We're cautiously optimistic."
Drexel University political science professor Bill Rosenberg said it's possible that the case could "get taken into the federal court system, away from the politics of Pennsylvania."
Contact David Gambacorta at email@example.com, 215-854-5994 and @dgambacorta.