The Supreme Court wrangled with a legendary mouse today, questioning how long Congress may extend copyrights on books, art, music, film and literature.

In 1998, heavily backed by such entertainment giants as The Walt Disney Co., Congress extended copyrights on existing works from the life of the author plus 50 years to the life of the author plus 70 years. For works owned by corporations, they extended the limit from 75 to 95 years. The law, named after the late singer and congressman Sonny Bono, forestalled the copyright expiration for the image of Mickey Mouse and other cartoon characters that would have expired early in the 21st century.

The law’s challengers say that the legislation, on top of past copyright extensions, amounts to a perpetual grant of copyright. These opponents, led by Internet publisher Eric Eldred, believe the law impedes the free flow of ideas the framers of the Constitution intended when they gave Congress the power to issue copyrights only for “limited times.”

Listening to today’s argument, the justices seemed concerned about the potentially endless copyright-extension legislation, but seemed undecided about what they could, or should, do about it.

“I can find a lot of fault with what Congress did,” Justice Sandra Day O’Connor said. “This flies directly in the face of what the framers of the constitution had in mind. But is it unconstitutional?”

Stanford University law professor Lawrence Lessig, arguing against the law, said there is no real difference between repeated copyright extensions and perpetual copyright.

However, Solicitor General Theodore B. Olson, representing the U.S. government, said the legislation struck a reasonable balance between the public’s right to eventual access and the constitutional directive “to promote the progress of the useful arts” by rewarding creative individuals for their efforts.

A decision in the case is expected by July.

— compiled from staff reports