By Ian Bush

PHILADELPHIA (CBS) — As Pennsylvania’s highest court considers arguments over the state’s voter ID law, a panel discussion on Monday at the National Constitution Center featured arguments for and against.

What does the Constitution have to say about voter ID?

“The United States Supreme Court has already upheld a voter ID law from the state of Indiana,” says Rutgers-Camden law professor Robert Williams. “So what the heck is the Pennsylvania Supreme Court doing reconsidering the matter?”

Williams says the decision leaves it up to all 50 states. For the justices here: “They want to see what’s unique in the Pennsylvania constitution,” he says.

Former Governor Ed Rendell says there’s no documented voter fraud, so what’s the rush for the new law?

“It’s within six weeks of the election,” says Rendell. “Why not stay this, let’s get it right, and then put it in place going forward?”

National Review columnist John Fund says every voter has the right not to have his or her pick canceled out by someone who shouldn’t be at the ballot box.

“It is in the interest of the government in a very close race, especially for president, to have a system that people have confidence in and believe has integrity,” he says.