The lawyer representing Pierre Konowaloff, the descendant of a Russian aristocrat contesting Yale’s ownership of Vincent van Gogh’s masterpiece “The Night Café,” has his legal roots here in New Haven.

According to new court documents filed by Yale last week, Allan Gerson LAW ’76 is representing the defendant, who claims to be the rightful owner of the painting. The new document says Konowaloff has until May 22 to respond to Yale’s suit, which the University filed against Konowaloff last Monday to assert its ownership of the piece.

Konowaloff claims “The Night Café” should be returned to him because, he argues, the seizure of the painting from his great-grandfather, Ivan Morozov, by the Russian government in 1918 was illegal. Yale says in its suit that the seizure, which was part of a larger nationalization of property by the Russian government, was legal and has been upheld in previous court cases.

Gerson, who previously worked for the U.S. Justice Department and currently practices at his firm AG International Law, recently wrote about cases of international disputes over art ownership. In February 2008, Gerson wrote an opinion piece in The New York Times criticizing a deal in which the British government agreed to offer Russia immunity over ownership disputes of 120 Impressionist and Modernist paintings, some of which, such as “The Night Café,” were seized by the Communists in the Bolshevik Revolution. Gerson said the British government was “complicit in the theft of private property.”

Gerson did not return requests for comment this weekend.

Gerson has handled several high-profile international law cases. After Pan Am Flight 103 was bombed, Gerson initiated the first suit against the Libyan government on behalf of the bombing victims. The victims, who Gerson helped represent, eventually reached a $2.7 billion settlement with Libya in 2003.

Gerson wrote a book about the case called “The Price of Terror: How the Families of the Victims of Pan Am 103 Brought Libya to Justice,” which was published in 2001.

Gerson also represented several victims of the Sept. 11 attacks in their suit against al-Qaida and others. He also represented U.S. victims of terrorists’ attacks in the Middle East in their suit against Arab Bank, which was accused of making payments to the families of suicide bombers. Both cases are still pending.