Another school year has begun at the University of Denver music department, renewing a familiar pattern for professor Lawrence Golan.

He instructed a nervous young conductor on the proper way to grip her baton. He patiently guided the orchestra through its second rehearsal of Jean Sibelius’s Symphony No. 5. He prepared for the season’s first concert.

But the fall also marks a culmination for Golan, whose 10-year trek through the legal system on behalf of fellow conductors, academics, film historians and others ends Wednesday at the Supreme Court.

Golan and his colleagues are asking the justices to overturn a decision by Congress giving copyright protection to millions of works by foreign artists that once were in the public domain.

Films by Alfred Hitchcock, paintings by Picasso and the symphonies of the great 20th-century Russian composers are among the works that are no longer available to be freely quoted, copied, played, shared or republished without paying royalties or seeking permission. In Golan’s case, that means he can no longer afford music that once was part of his basic repertoire.

Congress said that applying the copyright to such works was necessary to comply with treaties and foreign trade agreements and that the show of cooperation will mean copyright protection for the work of American artists overseas.

But those on Golan’s side — the ACLU, Google and the American Library Association, among others — say Congress’s action violated First Amendment rights, complicated efforts to digitize the world’s great libraries and obscured the original intent of the Constitution’s copyright clause: “to promote the progress of science and useful arts.”

“This case raises the question, ‘What is copyright really for?’ ” said Golan’s attorney, Anthony Falzone, of the Stanford Law School Center for Internet and Society. “Is it just something that benefits authors, or is it something that benefits society?”

Golan is a low-key, 44-year-old conductor who heads the University of Denver’s Lamont Symphony and the Yakima Symphony Orchestra in Washington state. He seems to defy the stereotype of the temperamental artist at the podium; he instructs a conducting student to be firm with her musicians but adds that there is nothing wrong with saying “please.”

He was recruited to be the lead plaintiff to show the real-life effects of Congress’s decisions, which fall mainly on small and community orchestras. He said he can think of no better example than what for many was probably their first exposure to classical music.

“ ‘Peter and the Wolf’ is one of the greatest, if not the greatest, pieces to introduce kids to music,” he said over dinner after a rehearsal. “We all saw it when we were kids. We took the field trip to the symphony downtown: The oboe played the duck, and the flute played the bird, and the horns played the wolf.”

Orchestras used to be able to buy the the Prokofiev symphony for $100, he said, and play it until the sheet music was worn out. Now it must be rented, at a cost of several hundred dollars for each performance.

Community orchestras and others playing for youth concerts won’t do it, he said.

“To see a live performance of ‘Peter and the Wolf,’ it’s just not going to happen,” Golan said. “The cost is just prohibitive.”

Falzone said Congress went beyond its powers in 1994 when it extended protection to works that the public had come to rely on.

“For 200 years, there was no question that once something entered the public domain, it belonged to the public,” he said. “They can never be taken back.”

The U.S. Court of Appeals for the 10th Circuit disagreed. “The government has demonstrated a substantial interest in protecting American copyright holders’ interests abroad,” the three-judge panel ruled, saying there was testimony of billions of dollars lost because foreign countries were not providing copyright protection.

The trade was to provide copyright protection for foreign artists.

And it rejected the plaintiffs’ argument that their First Amendment rights had been violated, saying speech rights do not draw “such absolute, bright lines around the public domain.”

For Golan’s supporters such as Google, the prospect that Congress has the ability to shield works in the public domain will chill its efforts to use the Internet to make accessible to the public “the vast stores of human knowledge and experience recorded in books,” the company told the court.

Its brief cites as an example its agreement to digitize the 7 million books in the University of Michigan’s libraries. “Even for a large company like Google, the possibility that works in the public domain will be legislatively deemed copyrighted in the future is a daunting and complicating prospect,” the brief said.

The Supreme Court in 2003 agreed that Congress had the authority to add 20 years to the copyright life of certain works. But it did not have to decide the question of whether works in the public domain could be protected.

New Obama administration Solicitor General Donald B. Verrilli Jr., in his first argument on behalf of the government, will defend the congressional action and echo the appeals court’s reasoning.

The protected work, he said in his brief to the court, was only in the public domain because it did not receive proper copyright protection at the time. Congress made provisions that those who relied on the work in the past could continue to have limited access to it.

Although it is rare for Congress to extend copyright protection to works in the public domain, he said, the very first Congress did so. And he disputes that a First Amendment interest develops just because works that should have received protection have been “exploited” in the past.

“A person who has previously engaged in the now-proscribed conduct has no ‘vested’ right to continue to do so,” Verrilli wrote.

Golan said he understands that copyright laws provide the means of making a living for those whose creations he admires. “This is certainly not a case against copyright,” he said.

But he argues that most composers would opt for having their music available in the public domain over earning small royalties for their descendants.

“I’m pretty sure they’d want their music played,” he said.

The case, Golan v. Holder , will be heard by an eight-member court because Justice Elena Kagan is recused. A tie would uphold the 10th Circuit’s decision.