The Recording Industry Association of America's campaign to bring copyright-infringing file swappers to justice has gone too far, according to one lawmaker, and as a result the organization has slightly changed its tune.

Sen. Norm Coleman (R-Minn.), chairman of the Permanent Subcommittee on Investigations, called the RIAA's tactic of subpoenaing thousands of users "excessive," and has scheduled hearings on the matter. In a response to Coleman's concerns, the music group promised that it was "gathering evidence and preparing lawsuits only against individual computer users who are illegally distributing a substantial amount of copyrighted music." Though the RIAA has said it would go after heavy users before, it also stayed vague on the subject of light downloaders.

It appears, however, that attempts to stop the heavy-duty abusers are failing. According to research by the NPD Group, file sharing has declined sharply since the RIAA's well-publicized shotgun-subpoena campaign started -- and especially since Verizon Communications (NYSE:VZ) lost a court battle to keep the names of its ISP subscribers private.

However, those households still swapping files are downloading even more than before. "Our data suggests that the RIAA's legal tactics have more of an effect on the attitudes and actions of lighter downloaders," said NPD's Russ Crupnick.

The RIAA has maintained a confident demeanor thus far, but this is a critical time in its efforts to stem the overwhelming tide of illegal music flowing through the Internet. Its subpoena campaign has raised awareness and curtailed the number of illegal file swappers at a time when decent legitimate options -- such as Apple Computer's (NASDAQ:AAPL) iTunes Music Store -- are finally available. We can expect another burst of publicity once the subpoenaed parties have been brought to trial or settlement.

This may be the industry's last, best chance to significantly alter music lovers' habits.

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