The Bush administration's top lawyer and the Christian Coalition threw their weight behind the entertainment industry Monday in a closely watched Supreme Court fight over file swapping.

Monday was the deadline for the Recording Industry Association of America (RIAA), the Motion Picture Association of America (MPAA) and their supporters to file their arguments with the nation's top court, in their efforts to reverse previous rulings that imposed only minimal legal restrictions on peer-to-peer software companies.

The entertainment companies have argued strongly in lower courts that Grokster and other file-swapping software companies should be held liable for the widespread copyright infringement of their users. In a lengthy brief, the U.S. Solicitor-general's office agreed.

"While P2P technology unquestionably can be employed for a variety of legitimate purposes without giving rise to rampant copyright infringement, the record...suggests that (the file-swapping software companies) have built their particular P2P networks around the 'draw' of massive copyright infringement," the Solicitor-general's brief read. They "cannot evade liability...merely by pointing to other, legitimate, uses of the technology."

The briefs filed by the record industry and movie studios were not immediately available Monday evening. The two trade organisations were scheduled to have a press conference early Tuesday to explain their strategy. File-swapping software companies Grokster and StreamCast Networks and their allies have until the end of February to respond.

Although focused on the issue of file swapping, the Supreme Court case is likely to be one of the most widely watched legal tussles in the technology world this year. Attorneys say the outcome of the case could affect virtually every consumer electronics or computer manufacturer, as well as software and entertainment companies.

At the case's heart is the 20-year-old Supreme Court ruling that made Sony videocassette recorders legal to sell. That decision said that technology that could be used for illegal purposes could still be legal to sell, as long as it had substantial commercial non-infringing uses.

The RIAA and MPAA say they're not trying to overturn that doctrine. But their attorneys have argued that because Grokster and Morpheus parent StreamCast Networks are aware of widespread copyright infringement on their networks, the companies should be held legally liable for that activity.

Two lower courts disagreed, saying that the file-swapping software companies did not have direct control over individual users' actions, or direct knowledge of individual trades.

A handful of diverse organisations joined the entertainment companies in filing with the Supreme Court on Monday, making for some strange bedfellows.

In addition to the Solicitor General's office, a group of conservative, family and Christian organisations that are often deeply critical of Hollywood and record label releases joined the chorus against file swapping.

Those groups, which included the Christian Coalition, the Concerned Women for America, Morality in Media and others, wrote that the lower court decisions relieving file-swapping companies of legal liability could lead to a "proliferation of anonymous, decentralised, unfiltered, and untraceable peer-to-peer networks that facilitate crimes against children and that frustrate law enforcement efforts to detect and investigate these crimes."

The Business Software Alliance, the Progress and Freedom Foundation, and a group of law professors also supported the RIAA and MPAA in their arguments.

A separate group of "neutral" parties also filed arguments on various issues surrounding the case.

U.S. Sens. Patrick Leahy, D-Vt, and Orrin Hatch, R-Utah, took issue with the file-swapping companies' attorneys characterisation of Congress' role in the recent copyright debates.

A larger group of Internet companies (including News.com parent CNET Networks) wrote that it did not approve of copyright infringement on the file-swapping networks but asked the court to retain the Sony decision since it had led to considerable technological innovation over the years.

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