Lorraine Minnite, a vote-fraud expert from Rutgers University, testified that the fraud the law was meant to deter was "exceedingly rare" and that there was no need for a voter identification law in Pennsylvania.
The ACLU, along with the NAACP and other voter and civil rights groups, sued the commonwealth on behalf of 10 Pennsylvanians who said they were disenfranchised by the law, passed in March, which requires voters to carry state-approved photo identification to the polls.
The law's Republican backers contend it is needed to prevent fraud; its opponents argue it is designed, instead, to create barriers for poor and minority voters, who tend to support Democrats.
During the last of six days of testimony in the case, plaintiffs attorney Jennifer Clarke of the Public Interest Law Center of Philadelphia asked Santana whether he was confident all of the city's 1.02 million registered voters could be informed of the law's requirements before the Nov. 6 election.
"No," he said. "The speed at which this is being enacted is not allowing us to adequately prepare."
Santana said problems that arose during the so-called soft rollout of the law during the April primary raised concerns about polling-place operations on Nov. 6. At the time, voters were simply told they would need identification in future elections.
Santana said the city was ordering 200,000 provisional ballots to distribute to all 1,687 polling places in order to accommodate the many voters expected to arrive without proper ID.
Under the new law, voters can cast ballots without their photo ID, but they must appear at county elections offices with proof of identification within six days after the election. If they don't produce valid ID, their ballots will be discarded.
As many as 361,000 Philadelphia voters may be ineligible because they have driver's licenses that expired before the cutoff date of 1990 or never had a license, Santana said, citing figures from the Department of State.
An Inquirer investigation published Sunday suggested those figures are likely significantly overstated.
Minnite, author of The Myth of Voter Fraud, testified that all the potential trouble was unnecessary given that the crime the law was meant to prevent was all but unheard of.
Voter impersonation - the type of fraud the law targets - is exceedingly rare across the nation as well as in Pennsylvania, she said.
Minnite has spent a decade studying the issue. Using federal statistics, she found only 26 instances of in-person fraud among 197 million ballots cast between 2002 and 2005, and, of those, about half were people who had felony convictions and were still under state supervision or were noncitizens. None misrepresented themselves at the polling place, Minnite said.
"There's a difference between making a mistake and intending to deceive," Minnite said.
She said evidence of voter fraud in Pennsylvania tracked the national picture and that in virtually all the cases she found, none would have been resolved by having a photo identification law.
"Every way I looked at it, I couldn't find evidence that this was a problem we should be legislating against," Minnite said.
The commonwealth and the plaintiffs agreed going into court that there had been no investigations or prosecutions of voter fraud in Pennsylvania.
The commonwealth contends the law is designed to prevent future fraud.
Closing arguments in the case are scheduled for Thursday. Commonwealth Court Judge Robert Simpson told lawyers he will likely issue his ruling the week of Aug. 13.
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