The special counsel will leave behind a complex legacy, having amassed considerable evidence against Donald J. Trump but having lost key legal battles that could constrain future investigators.

Smith is still fighting the judge's decision to dismiss Trump's indictment, although he has dropped the classified documents case.

An appellate court on Tuesday granted special counsel Jack Smith's request to terminate his appeal against Donald Trump related to classified documents, bringing to a close the second of the Justice Department's two criminal prosecutions against the president-elect.