A sign advertising gas prices is seen at a Chevron station in Los AngelesChevron Corp urged a U.S. appeals court on Monday to uphold a ruling finding that an American lawyer used corrupt means to secure a $9.5 billion pollution judgment in Ecuador.A lawyer for Chevron told the 2nd U.S. Circuit Court of Appeals in New York that Steven Donziger, a U.S. lawyer who represented a group of Ecuadorians that sued the oil giant, pursued a case “shot through with fraud.” “What happened here was a fraud on the Ecuadorian courts,” Theodore Olson, Chevron’s lawyer, said. “The problem is, how do you write an opinion that does not open the door to attacks on judgments from around the world?” Deepak Gupta, Donziger’s lawyer, said.The appeal follows years of litigation by the villagers, who sued Texaco, which Chevron later acquired, over contamination in the jungle around Lago Agrio, Ecuador, between 1964 and 1992.The Ecuadoreans initially sued Chevron in federal court in Manhattan in 1993.