When the district attorney, Cyrus R. Vance Jr., a Democrat, first brought charges against Mr. Manafort in March 2019, it was widely understood that he was doing so to make sure that Mr. Manafort would face prosecution even if Mr. Trump decided to pardon him.

At the time, Mr. Manafort was serving a sentence of seven and a half years in a Pennsylvania federal prison after being convicted at a 2018 financial fraud trial by prosecutors working for the special counsel Robert S. Mueller III.

In October, a New York appeals court found that Mr. Vance’s efforts to try Mr. Manafort violated the state’s double jeopardy law. Mr. Vance took the case to the Court of Appeals.

Then, in December, Mr. Trump did pardon Mr. Manafort, 71, who had been released to home confinement in Northern Virginia, after his lawyers argued that he was at risk of contracting the coronavirus.