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.

Notably, the Fifth Circuit’s decision had split with two other federal appeals courts that upheld the law.

The Supreme Court said that it will leave the stay in place until deciding whether to hear the merits of the private regulator’s appeal. It requires the votes of four justices to grant a petition for writ of certiorari, or review.

An association of thoroughbred owners challenging the law says that it will “acquiesce” to the court taking up the case to resolve the split among the circuits.

“The Horsemen recognize that acquiescence to certiorari is rare; the normal course is to defend one’s favorable judgment below from further review,” the racehorse owners said. “In this instance, however, certiorari just makes sense.”

Justice Ketanji Brown Jackson was the lone dissenter to Monday’s order.

“[W]hatever the stay factors might portend, I see no reason for us to intervene in an emergency posture,” she wrote. “I would therefore deny the application and promptly proceed to consider the pending petition for certiorari.”

Signed into law by President Donald Trump in 2020, HISA empowered the private Horseracing Integrity and Safety Authority to establish a nationwide regulatory scheme for the horse-racing industry. The authority, consisting of a nine-member board of industry and nonindustry members, was given the power to implement rules to promote track safety, medication controls and antidoping regulations.

The legislation was a response to a high number of incidents plaguing the world of horse racing. In 2019, for instance, Congress found that 441 thoroughbreds died from injuries related to racing, a far greater fatality rate than in other parts of the world.

The law has been the subject of extensive litigation since its passage and was amended after an earlier ruling by the Fifth Circuit that the authority’s rulemaking power was not supervised by any governmental agency. Congress amended the law in 2022, signed by President Joe Biden, subjecting the authority to more oversight by the Federal Trade Commission.

But over the summer, a panel of the Fifth Circuit again found the law unconstitutional, focusing this time on the authority’s enforcement powers under the law.

“The statute empowers the Authority to investigate, issue subpoenas, conduct searches, levy fines, and seek injunctions—all without the FTC’s say-so,” the panel held. “That is forbidden by the Constitution. We therefore DECLARE that HISA’s enforcement provisions are facially unconstitutional on that ground.”

In September, the authority, represented by lawyers at Akin Gump Strauss Hauer & Feld and Ransdell Roach & Royse, filed an application to pause the effect of the Fifth Circuit ruling in the Supreme Court.

If allowed to stand, the Fifth Circuit’s decision “would plunge horseracing back into a confusing web of varying enforcement protocols, disrupt the entrenched expectations of a national industry that has adjusted to the federal reforms over two-plus years, and imperil the human and equine athletes who have been protected by the successful programs Congress directed,” the authority wrote. “The data are clear: more horses would die and more cheaters would prosper.”

In contrast to the Fifth Circuit, the U.S. Court of Appeals for the Sixth Circuit upheld the law and rejected the notion that it violates the so-called private nondelegation doctrine, under which there are limits to how much authority Congress can delegate to a private entity. The Sixth Circuit found that the arrangement between the FTC and HISA to be analogous to the securities industry, where self-regulating bodies, such as the Financial Industry Regulatory Authority, are supervised by the U.S. Securities and Exchange Commission.

“Sometimes government works,” Sixth Circuit Chief Judge Jeffrey Sutton wrote for the court last year.

The request for stay and petition for review are docketed at the Supreme Court as Horseracing Integrity and Safety Authority v. National Horsemen’s Benevolent and Protective Association, No. 24A287 and No. 24-433.