(CNN) In a case involving a Nazi confiscation of a Jewish family's painting, the Supreme Court on Tuesday grappled with how federal courts should decide whether California law or a foreign country's law should apply.
The case, which was filed in federal court in California, is now before the Supreme Court after nearly 17 years of litigation.
The descendants of Jewish Holocaust survivors are seeking the return of a painting that their family was forced to hand over to the Nazis and that eventually ended up in a public Madrid, Spain, art museum.
The art piece at the center of the case is a 1897 French Impressionist work by the famed painter Camille Pissarro titled "Rue Saint Honoré, Afternoon, Rain Effect."
It was owned by the Cassirer family in Germany until 1939, when Lilly Cassirer Neubauer was forced to hand it over to the Nazis in order to obtain an exit visa she needed to flee the country. A Nazi art dealer confiscated the painting in exchange for $360 that was put in an account that Neubauer could not access. In the decades that followed, a series of sales and trades took the painting to California, then to a gallery in New York, from where it was purchased by a Swiss collector who eventually sold much of his collection, including the painting, to the foundation, which he set up with the Spanish government.
A lawyer for the art foundation, the Thyssen-Bornemisza Collection, asked the Supreme Court to set out a "fair and balanced way" for federal courts to approach these kinds of cases, as different states have different legal tests that could be applied, depending on where the family had brought the case.
"Welcome to United States. That's how the courts work," Chief Justice John Roberts told the foundation's lawyer Thaddeus Stauber. "And a private citizen of the United States who moves from New York to Ohio, the law that applies to him is going to change as well."
The case was brought by Lilly Cassirer Neubauer's grandson Claude Cassirer, who retired in California. He filed the lawsuit in 2005 after learning the painting was on display at the Thyssen-Bornemisza Museum after the foundation rebuffed his other efforts to have the painting returned.
The dispute before the Supreme Court turns on how federal courts should decide -- under the Foreign Sovereign Immunities Act, which sets limits on when a foreign entity is immune to litigation -- whether to apply a state law or the law of the foreign country.
The Cassirer family -- now being led in the litigation by Claude's children after Claude died in 2010 -- are making claims under a California law that they say makes them the rightful owners of the painting, because of how the artwork was obtained. But the lower courts have instead used legal tests that have led them to apply a Spanish law where the burden is higher on victims to prove that the foundation should have known the painting had been stolen.
During the oral arguments, the lawyer for the Cassirer family, David Boies -- who participated in the hearing remotely -- faced tough questions about whether federal law required the lower courts to treat the case differently than it did.
The US Solicitor General's office, represented by Masha Hansford, also participated in the hearing, making friend-of-the-court arguments supporting the Cassirer family.
The arguments focused on the highly technical aspects of the case, concerning the legal tests that federal courts should use in lawsuits brought against foreign states and their instruments to decide which laws should apply. Only once was the painting itself referenced by the justices.
"I think everyone can agrees that this is a beautiful painting," Justice Stephen Breyer said.
Justice Sonia Sotomayor, as has become her custom in recent weeks, participated in oral arguments via telephone.