Congress: "Treats authors even-handedly"

Various groups, including the non-profit-making Internet Archive, are arguing for quicker access to copyright material to take advantage of digital technology.

But the US Government has so far urged courts to protect authors' current legal status.

Solicitor General Theodore Olson has written to the court to say that, because copyrighted material can be used under some circumstances - so-called "fair use" - the "concerns and values reflected in the First Amendment are therefore fully satisfied."

But a recent move to extend the life of copyright from 50 years to 70 years after death - which brought the US in line with the European Union - has led to criticism that the law is preventing reasonable access to old books, movies and songs.

'Restraint'

Lawrence Lessig, attorney for the challengers, said the 20-year extension approved by Congress in 1998 was ill-timed and unconstitutional.

"Just as the time that the internet is enabling a much broader range of individuals to draw upon and develop this creative work without restraint, extensions of copyright law are closing off this medium to a broad swath of common culture," he said.

Digital technology: New archiving opportunities

And law professor Mark Lemley has pointed out that Congress extended the term of copyright 11 times in the past century.

In a submission to the Supreme Court, Mr Lemley argued that the current law meant copies of old books, films and sound recordings were being lost before they could be archived.

Suggesting the digital archiving of old works, Mr Lemley said that under current law "we must continue to wait, perhaps eternally, while works disappear and opportunities vanish".

The Bush administration said that giving creative people the rights to their material promoted progress, and defended the 1998 decision to apply the 20-year extension to all current copyrighted material, not just future works.

"Congress was entitled to establish a system of copyright that treats authors in a more even-handed fashion," wrote Solicitor General Theodore Olson in the government submission.