On Friday, Rep. Rick Boucher, D-Va., sent a letter to executives of the recording industry's trade association, asking whether anti-piracy technology on CDs might override consumers' abilities to copy albums they have purchased for personal use.

A 1992 law allows music listeners to make some personal digital copies of their music. In return, recording companies collect royalties on the blank media used for this purpose. For every digital audio tape (DAT), blank audio CD, or minidisc sold, a few cents go to record labels.

"I am particularly concerned that some of these technologies may prevent or inhibit consumer home-recording using recorders and media covered by the" Audio Home Recording Act (AHRA), Boucher wrote. "Any deliberate change to a CD by a content owner that makes (the allowed personal copies) no longer possible would appear to violate the content owner's obligations."

The Capitol Hill attention is a potentially daunting sign for recording companies, which are becoming bolder in their efforts to keep consumers from making unauthorized copies of CDs. Each of the major record labels has said it is looking at several versions of new anti-copying technology; in particular, Universal Music Group executives have said they want to protect a large proportion of their new releases as soon as midyear.

The labels are worried that the rise of home CD-burners has eaten into album sales, particularly after the worst year in a decade for the music industry.

Universal was the first major label to openly distribute a copy-protected CD in the United States, with the release of a soundtrack to the "Fast and the Furious" film in December. Companies that produce copy-protection technology say other albums have been quietly released into the market, but verified sightings have been rare.

The AHRA issue had been spotlighted by a few copyright attorneys for several months, but until now it has not been a large part of the debate over copy protection.

"If you put technology in place that prevents people from using their recording devices, then it seems that you should not be eligible for the royalty payments" under the AHRA, said Fred von Lohmann, a staff attorney with the Electronic Frontier Foundation.

A representative for the Recording Industry Association of America had no immediate comment on Boucher's letter, saying the group had not yet seen it.

Boucher, who has been a legislative opponent of the big recording companies for some time, asked the industry group to respond to a long list of questions describing the technologies the record labels are using. He stopped short of saying what he might do if he decided that the technologies do violate the terms of the 1992 law.