On December 8, 1997, in a sharply divided opinion, the United States Court of Appeals for the District of Columbia Circuit ruled that the Endangered Species Act (ESA), as applied to a subspecies of a fly found in only two California counties, is a proper exercise of federal power under the Commerce Clause of the Constitution. On June 16, 1997, WLF filed a brief with the Court urging it to overturn a lower court decision that had upheld federal regulation. The lower court ruled that because the government proved that two botanists traveled across state lines to visit the fly’s habitat, Secretary of Interior Bruce Babbitt had authority under the Commerce Clause of the Constitution to prevent a county hospital as well as other structures from being built in the habitat area. WLF argued in its brief that Congress has no authority to regulate local land use activity with regard to the fly.