WASHINGTON -- U.S. District Judge John D. Bates heard arguments Thursday morning on Verizon's latest legal maneuver to avoid complying with a Recording Industry Association of America (RIAA) subpoena requesting the name of a Verizon Internet subscriber who allegedly downloaded more than 600 copyrighted music files in a single day.

Citing provisions in the Digital Millennium Copyright Act (DMCA), Bates last month ruled Verizon had to turn over the name to the RIAA, a decision Verizon immediately appealed. Verizon also asked Bates to to stay the ruling in hopes of maintaining the status quo until the appeal process is resolved.

The RIAA, however, is insisting Verizon immediately comply with the court order regardless of the appeal process.

After Thursday's two-hour hearing, Bates didn't issue a ruling but promised to "get something decided pretty expeditiously."

Verizon's legal team told Bates that if the phone company is forced to reveal the name of the alleged infringer, it would suffer "substantial good will harm" and raised a host of legal issues involving the validity of the subpoena, which was issued under a controversial provision of the DMCA. Unlike a usual subpoena, which requires some underlying claim of a crime and must be signed by a judge or magistrate, under the DMCA a subpoena can be issued by a court clerk without presenting evidence of a crime being committed.

The DMCA subpoena compels an Internet service provider (ISP) to turn over the name, telephone number and address of a subscriber.

The RIAA said it would be its music publishing company members that would suffer the most harm if Bates decides to allow Verizon to shield the name until the appeal process is over because of the inability to "act against copyright infringers."

A ruling in Verizon's favor, the RIAA argued, will allow the company to put a "freeze on all subpoenas until the appeal is final." The RIAA also revealed for the first time 10 such DMCA subpoenas have been served on ISPs and Verizon is the first to not to comply.

Last month, John Thorne, Verizon's senior vice president and deputy general counsel, said the company felt compelled to seek a court-ordered stay when RIAA officials refused to agree to a voluntary stay.

"Verizon will use every legal means to protect its subscribers' privacy," Thorne said. "The recording industry brought this case as a 'test case' of its aggressive legal theories. We are seeking a stay so that the Court of Appeals can issue a final ruling on the critical legal issues before we are required to turn over a subscriber's identity."

Matthew Oppenheim, senior vice president of business and legal affairs for the RIAA responded to the stay request by saying Verizon "should not be permitted to ignore a law."

Oppenheim added, "It's a shame that Verizon has resorted to mischaracterizations and consumer scare tactics, a trait we understand they are well known for in public policy debates. Just ask some of the small, local telephone and DSL providers."

The RIAA in August asked a federal district court to enforce the subpoena, which seeks information related to "a computer connected to the Verizon network that is a hub for significant music piracy." The motion said Verizon is the only entity that can identify the infringer behind the computer.

Verizon refused to comply with the subpoena, arguing it didn't think the subpoena request met the circumstances that the DMCA allows for in compelling information in order to protect against piracy. Verizon contended the subpoena related to material transmitted over Verizon's network, but not stored on it, and thus fell outside the subpoena power authorized in the DMCA.

In ruling in the RIAA's favor, the court concluded, "that the subpoena power ... applies to all Internet service providers within the scope of the DMCA, not just to those service providers storing information on a system or network at the direction of a user."

In announcing its appeal, Sarah B. Deutsch, vice president and associate general counsel for Verizon, said, "The court's decision has troubling ramifications for consumers, service providers and the growth of the Internet. It opens the door for anyone who makes a mere allegation of copyright infringement to gain complete access to private subscriber information without the due process protections afforded by the courts."