SAN FRANCISCO (Salon.com) - In a fresh attack on DeCSS, a program that decrypts DVDs so people can play them on Linux-based operating systems, the Motion Picture Association of America filed a motion on Wednesday to prohibit 2600, the ''hacker quarterly,'' from linking to other sites that post copies of the outlawed program.

Specifically, says Mark Litvack, the MPAA's vice president and director of legal affairs for worldwide anti-piracy, the organization representing movie studios wants Eric Corley -- aka Emmanuel Goldstein, publisher of 2600 -- to quit ``trafficking'' in the distribution of DeCSS.

In January, a federal judge prohibited 2600 and two other sites from posting DeCSS. (The judge had ruled that DeCSS was a violation of the 1998 Digital Millennium Copyright Act, which considers anything that subverts ``access control mechanisms'' to digital content to be illegal -- regardless of whether the modifications to the mechanism are used to access the content or to copy it.) Now the MPAA is trying to keep 2600 from even linking to other sites that have posted the program.

But wait. Can hyperlinks be outlawed? Only last week, a California judge ruled, in a case brought by Ticketmaster against Tickets.com, that it's not illegal for one site to link to another.

Among other things, that suit concerned ``deep linking.'' Ticketmaster alleged that by bypassing its home page and linking directly to ``inside'' pages, Tickets.com violated its copyright. The judge, however, held that ``hyperlinking does not in itself involve a violation of the Copyright Act.''

The MPAA motion is focused on a different aspect of linking --whether it's legal to link to information that a judge has ruled is illegal to post -- but the Ticketmaster vs. Tickets.com case may still lend some legal precedent.

Daniel Harris, the attorney who argued for Tickets.com's practice of linking to pages deep within Ticketmaster's site, says the case should indeed be considered a precedent in New York's federal district court, where the DeCSS case sits.

``The Internet's exponential growth is due in part and parcel to the access to linked information,'' says Harris, a partner at the Palo Alto, Calif., firm Brobeck, Phleger & Harrison. ``Once you start applying the ability to police where links go, then it's going to have major negative ramifications on how the Internet will grow in the future.''

Of course, the MPAA says its only concern is with the DeCSS case, not linking policies in general. ``There is certain hyperlinking that is clearly legal and others that aren't,'' says Litvack, adding that links to DeCSS are like links to child pornography, which ``no one would want to proliferate, even if it's linked and not simply posted.''

But whether you believe decryption technologies are as bad as kiddie porn or not, chances are you'll be able to get DeCSS without too much trouble. Since it was first made available by European hackers last year, DeCSS code has been posted and linked to from hundreds of Web sites.

The MPAA's motion on Wednesday cites 300 links, and Litvack says there are probably even more. Meanwhile, in the non-virtual world, some activists have even taken to the streets, posting the code on posters and T-shirts. And adding further insult to injury, one free-software fan even created a decoy to fool investigators, like those at the MPAA, who are scouring the Web for sites posting the code.

The MPAA's Litvack remains positive: ``This is a country of laws,'' he says, ``and you have to hope people will obey them.'' But there aren't many laws that govern the Internet, and until the MPAA's motion and others make it through court, it's not clear where the law stands on linking.

Meanwhile, legal decisions are having scant effect on the spread of DeCSS. ``The MPAA is really running uphill and constantly being blown backwards,'' says Harris. ``The genie's out of the bottle, and they're trying to stuff him back in.''

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