By Cherri Gregg and Dray Clark

HARRISBURG, Pa. (CBS) —  Is the requirement to show an official form of ID a legitimate anti-fraud measure or an attempt to suppress voter turnout?

That’s the issue that came under scrutiny today in a Harrisburg courtroom, where the American Civil Liberties Union is trying to have Pennsylvania’s nascent voter ID law overturned.

The courtroom was standing-room-only today as opening statements were presented.  The complete presentation by both sides took just over one hour.

Lawyers for the ACLU, carrying the burden of proof, argued that the Pennsylvania voter ID law, as written, disenfranchises hundreds of thousands of voters and should be struck down.  They claim that the measure unduly restricts voters to a narrow list of what constitutes an “acceptable” ID.

They also argued that the most popular form of ID card — driver’s licenses or similar ID cards issued by Penndot — are not easy to obtain for many people.  They pointed out that Pennsylvania has 9,300 polling places but only 71 Penndot licensing locations.  They said that more than half of the state’s counties have “limited” Penndot licensing locations, or none at all.

Attorneys for the Commonwealth of Pennsylvania spent about 15 minutes outlining their case, focusing on US Supreme Court rulings which they say confirms that the concept of voter ID laws is Constitutional.  They say additional Supreme Court case law backs their contention that requiring acceptable forms of voter ID is not an impermissible burden on voters.

In addition to opening statements, the court also heard prerecorded statements from two witnesses.  Proceedings resume tomorrow.  State employees and impact experts are expected to testify at some point.