WASHINGTON, D.C. --- The U.S. Supreme Court on Tuesday heard arguments from an attorney representing 23,000 gasoline distributors, alleging that Texaco and Shell Oil violated antitrust laws and fixed prices through joint ventures in the late 1990s. The joint ventures are now defunct. According to a report in the Los Angeles Times, the justices appeared unconvinced by the attorney's presentation. Chief Justice John Roberts called the gas distributors' arguments "a very artificial hook." The other justices, including David Souter and Stephen Breyer, expressed the view that the price appeared to be set by a legitimately formed venture. The case dates back to 1998, before Texaco was purchased by Chevron. That year, Texaco and Shell joined forces to form Equilon Enterprises and Motiva Enterprises to refine and market their gasoline. The two ventures charged the same wholesale price for Texaco and Shell gasoline, sold separately under the two different brand names, the L.A. Times reported. A number of gas distributors filed a class-action suit in California in 1999. In court papers, they claim to have paid at least $1 billion in excessive charges.