WASHINGTON (Reuters) - Verizon Communications VZ.N said it would ask a federal appeals court on Thursday to strike down a judge's order to turn over the name of a customer suspected of downloading free music over the Internet.

Verizon lawyers were to file documents with the U.S. Court of Appeals for the District of Columbia later on Thursday, arguing that the order is unconstitutional and would hobble privacy on the Internet, a company executive said at a press briefing.

"I see a grave jeopardy of privacy for people who are not doing anything wrong," said John Thorne, Verizon's deputy general counsel.

The company also filed a motion with the lower court judge, U.S. District Judge John Bates, asking him to stay his Jan. 21 ruling while the case is under appeal.

Verizon will argue that Bates's reading of the 1998 Digital Millenium Copyright Act violates constitutional rights to privacy and anonymous speech, Thorne said.

Under Bates's interpretation, Thorne said, "strangers, stalkers, telemarketers, pollsters, creditors and anybody else" could obtain the identity of almost any Internet user.

He cited an example in which a contractor, working on behalf of one of the record companies, mistakenly singled out a child's Harry Potter book report as an illegal download and automatically filed for a subpoena.

"No matter where you go, your identity can be compelled to be revealed under this process," Thorne said.

In his ruling, Bates found in favor of the music industry's trade group, the Recording Industry Association of America. He ordered Verizon to turn over the name of a customer suspected of downloading more than 600 songs in one day over the Internet.

Bates said Verizon must cooperate with recording industry efforts to track down online song swappers.

An RIAA official said on Thursday the organization would fight the appeal and dismissed Thorne's comments as "mischaracterizations and consumer scare tactics."

"Instead of attempting to delay the enforcement of this decision, Verizon would be better served by doing its part and helping us combat the billions of illegal downloads that are depriving musicians, songwriters, record companies, retailers and countless others of their fair due," said Matthew Oppenheim, a senior vice president at RIAA.

CUTTING INTO DISC SALES

The case could set an important precedent as the recording industry asks schools, businesses and Internet providers to help them track down individuals who they believe are cutting into compact disc sales by trading digital songs through "peer-to-peer" services like Kazaa.

Under the 1998 digital copyright law, Internet providers have voluntarily shut down Web sites that contain infringing material, but they have balked at requests to disconnect users who trade songs with each other directly over swapping networks.

The industry has also accused Internet providers of profiting from illegal downloading. Recording-industry investigators, using automated software, have been able to track down the numerical Internet addresses of file traders, but have not been able to match those addresses with individual names.

Thorne said the Recording Industry Association of America was anticipating a heavy volume of requests and had asked permission to tap directly into Verizon's computers "to facilitate the extraction" of subscribers' identities.

"Verizon's answer to that is no," Thorne said.

Oppenheim, of the RIAA, disputed that account. He said the trade group offered to help properly format the data to make it less burdensome for Verizon to comply with the court ruling.

The RIAA represents the five largest recording companies: AOL Time Warner's AOL.N Warner Music; Sony Corp.'s 6758.T Sony Music; Bertelsmann AG's BERT.UL BMG; Vivendi Universal's V.N Universal Music Group; and EMI Group Plc EMI.L .