Nick Wing has a good entry at the Huffington Post, "Pennsylvania Voter ID Law Trial Set Today as State Concedes It Has no Proof of In-Person Voter Fraud." It starts:
Defendants in a case against one of the nation's strictest voter ID laws in Pennsylvania made a major concession to plaintiffs this week, just days ahead of the start of the trial over the measure.
In a stipulation agreement signed earlier this month, state officials conceded that they had no evidence of prior in-person voter fraud, or even any reason to believe that such crimes would occur with more frequency if a voter ID law wasn't in effect.
That's a major point to concede -- that there's no evidence. If this were really a problem surely there would be some evidence. I know one of the City Commissioners in Philadelphia has one possibility -- two voters with different forms of the same name, voting in two different polling places, using fictitious addresses. But even if this does turn out to be voter fraud there's no reason to believe that person doesn't have an id for each name and address.