Unruly air passenger rates declined in the U.S. after mask mandates were suspended.

The number of unruly air passenger incidents reached their lowest level since 2020 after a federal judge in Florida struck down a government mask mandate on public transportation.

The agency reported 1.9 incidents per 10,000 flights during the week ending April 24, down from 4.2 incidents per 10,000 flights a week earlier. It didn't say why the drop happened.

The former F. A.A. administrator Steve Dickson implemented a zero-tolerance policy against unruly passenger behavior in January, which resulted in hefty fines instead of the warning letters or counseling that were used in previous policies.

The F.A.A. recommended record fines for two passengers on flights operated by American Airlines and Delta Air Lines. One woman was accused of spitting at, head-butting and biting a crew member, while another tried to hug and kiss the passenger seated next to her before walking to the cabin door and trying to leave the plane.

The unruly passenger rate dropped by more than 60 percent after the F.A.A. implemented its zero-tolerance policy. The rate fell further after the mask mandate was lifted.

70 percent of unruly passenger incidents involved the enforcement of masking rules.

Billy Nolen, the acting administrator of the F.A.A., said in a statement last month that "having dangerously on a plane will cost you."