The former acting New York U.S. attorney said Adams' attorneys had offered "what amounted to a quid pro quo" — helping the U.S. with immigration enforcement "in exchange for dismissal of his case."

Federal prosecutors acted after a Justice Department directive said the case hindered President Trump's crackdown on illegal immigration.

The federal case against Mayor Eric Adams has gone through a roller coaster of events since he became the first sitting New York City mayor to be indicted.