Foie gras, the culinary delicacy that comes from the enlarged livers of ducks and geese that have been force-fed corn, is back on the menu in California after a federal judge on Wednesday struck down the state's controversial law banning its production and sale.Reuters reported that while some California chefs planned to celebrate the return of fatty duck liver, animal rights activists said the state's hard-fought foie gras battle was far from over.California's bill outlawing foie gras passed in 2004 but the ban didn't go into effect until 2012.Foie gras producers and restaurants for years have lobbied to remove the ban, which gave rise to underground "Duckeasies" that offered free foie gras or sold it as unlisted menu item.In their latest legal battle, Canada's Association des Eleveurs de Canards et d'Oies du Quebec, New York's Hudson Valley Foie Gras and Los Angeles-based Hot's Restaurant Group argued that California's sales restriction ran afoul of federal law and the U.S. Constitution.And on Wednesday, U.S. District Court Judge Stephen Wilson ruled that the ban was at odds with federal law overseeing the sale and distribution of poultry products."California cannot regulate foie gras products' ingredients by creatively phrasing its law in terms of the manner in which those ingredients were produced," Wilson wrote."It's a good day for restaurants," said Jot Condie, president and chief executive of the California Restaurant Association, a long time foe of the ban. "Turning chefs into criminals is not something we support."But Paul Shapiro, vice president of farm animal protection for the Humane Society of the United States (HSUS), predicted that the celebrations could be short lived. HSUS and other animal rights groups vowed to ask California's attorney general to appeal Wednesday's ruling."The state clearly has the right to ban the sale of the products of animal cruelty," said Shapiro, who expects the federal appeals court to uphold the law as it did in the previous round of litigation.In August 2013, the 9th U.S. Circuit Court of Appeals upheld California's foie gras law, rejecting opponents' assertion that it violated the U.S. Constitution's Commerce Clause, which prohibits states from interfering with interstate commerce. In October 2014, the U.S. Supreme Court declined to hear their appeal, a move that allowed the ban to stand.Chef Josiah Citrin of Melisse, one Los Angeles' top restaurants, has been an outspoken critic of the ban and plans to serve his legal, personal stash of foie gras to diners tonight."It's nice to have some culinary freedom back ... I plan to have it on the menu as long as it's legal," Citrin said.