By Cherri Gregg

HARRISBURG, Pa. (CBS) — Pennsylvania’s Secretary of the Commonwealth was on the witness stand today, during day five of the court hearing on Pennsylvania’s new voter ID law.

And her testimony just added to the confusion over exactly how many voters need ID.

Secretary of the Commonwealth Carole Aichele is the top state official in charge of implementing the voter ID. But when she took the stand she was cagey, even making jokes in some instances in her response to plaintiffs’ attorneys.

At one point, when lawyers asked her about the details of the voter ID law, Aichele responded, “I don’t know what the law says.”

Plaintiffs’ attorney David Gersch (of Arnold and Porter) says the secretary is not the only one confused about what the law requires.

“The law is very technical — that’s another problem with it,” he tells KYW Newsraadio. “Earlier in the trial we had testimony from lawyers who are advocates for poor people and homeless people trying to get identification, and those lawyers said they didn’t understand all apects of the law!”

When lawyers questioned Aichele today about the number of Pennsylvanians who need ID, Aichele was adamant that 99 percent of voters had valid ID.

When plaintiffs’ attorneys cited earlier Department of State testimony that the number is likely inaccurate, Aichele said simply, “I disagree.”

She later admitted that the state does not know the real number of voters who need ID.

Recent Pennsylvania Department of State figures estimate that possibly three-quarters of a million voters may not have the needed ID and another half-million have ID that will be expired by November.

Aichele also testified about the state’s efforts to educate voters on the law. She conceded that the state has repeatedly advised eligible voters to get a secure Penndot ID, which requires a raised-seal birth certificate and other documentation.

Gersch says that’s part of the problem.

“No one really believes that you need all of that documentation in order to vote,” he says. He says you only need to be over 18, a US citizen, and a resident of the state, so requiring additional documentation is unlawful.

“There is really no need to be putting people through all the hurdles involved with getting a Penndot ID,” he says.

Aichele (whose husband, Stephen, is Gov. Corbett’s chief of staff) testified that Penndot IDs are useful for many functions but the new, free state voter ID that will launch next month (see related story) lowers the standard to comply with the new voter registration requirements.