In one of the longest-running art restitution disputes in the US, the descendants of Lilly Cassirer, who fled Nazi Germany with her husband in 1939, are fighting tooth and nail against Madrid’s Thyssen-Bornemisza Museum to reclaim Camille Pissarro’s ‘Rue Saint-Honoré dans l’après-midi. Effet de pluie’ (1897).

The Cassirer family claims that Lilly and her husband were forced to trade the £24 million French Impressionist work for their exit visas in order to escape persecution. The painting changed hands between numerous art dealers and collectors over the course of a decade before finally arriving in Spain in 1993. When the Cassirers finally found the painting in a museum catalogue in 1999 they requested its return. The Museum refused and the family filed suit, commencing legal proceedings which have ensued for the past 16 years.

The case returned to court on Monday (5 December 2016) following a 2015 ruling by the US District Court in Los Angeles, which dismissed the Cassirer family’s claim. In an appeal led by Lilly’s great-grandson, David Cassirer, the family is challenging the judgment of the Los Angeles court, which held that Spanish law prevails over Californian law. In Spain, a museum which publicly owns and displays a stolen work for over 6 years can be deemed its legal owner.

The Cassirer family is being represented in the appeal by New York lawyer David Boies. Referring to the illicit trafficking of cultural property by ISIS, Boies describes the Pissarro case as “critically important not only in terms of trying to right terrible wrongs that had their origin in the Nazi persecution of the Jews but also to establish principles that are very important to what’s happening now in the world”.

Boies is arguing that the Museum could be considered an accessory to the theft of the Pissarro because it either knew or ought to have known it was stolen. He told the judges gathered in Pasadena’s Ninth Circuit Court of Appeals on Monday that a torn label on the painting which showed it had been in Berlin coupled with a gap in provenance information between 1939-1976 ought to have raised red flags.

Boies also told the court that even if the Cassirer family is unable to reclaim the physical painting, under Spanish law they are entitled to damages.

Lawyer for the defense, Thaddeus J. Stauber, rejected the suggestion that the Thyssen-Bornemisza Museum is an accessory to theft because this is no longer defined as receiving stolen property under the Spanish legal code. Conceding that the painting was “lost in tragic circumstances” Stauber nonetheless contended that the Cassirer family “have asked us to suspend reality.”