“We voted to dismiss these matters as an exercise of our prosecutorial discretion,” Mr. Cooksey and Mr. Trainor wrote.
The Cohen case captured the public’s attention in 2018 after the F.B.I. raided his office, apartment and hotel room, hauling off boxes of documents, cellphones and computers. Months later, Mr. Cohen pleaded guilty to, among other charges, campaign finance violations.
He said in court that he had arranged payments — including $130,000 to the adult-film actress Stormy Daniels, whose real name is Stephanie Clifford — “for the principal purpose of influencing the election.”
The payment was far in excess of the legal limit for individual contributions for president, which was then $2,700.
Mr. Cohen further said he had arranged for a $150,000 payment by American Media Inc. to Karen McDougal, a former Playboy playmate, earlier in 2016.
Mr. Cohen would later turn on Mr. Trump and write his own book about serving as the former president’s enforcer while he was a businessman. The book was called “Disloyal: A Memoir.”