The U.S. Supreme Court on Monday temporarily paused an appeals court decision striking down a recent horse-racing safety law passed with bipartisan support in Congress, averting what a private regulatory body warned would be a "'Wild West' vacuum" imperiling horses and emboldening cheaters.

In an 8-1 vote, the court stayed the conservative U.S. Court of Appeals for the Fifth Circuit's ruling that the law is unconstitutional. The Fifth Circuit held that the Horseracing Integrity and Safety Act violates the separation of powers by giving a private regulator too much power over one of the nation's oldest sporting and gambling pastimes.