Donald Trump has issued a full pardon to Scooter Libby, a former top aide to vice president Dick Cheney.
Libby, who was Mr Cheney's chief of staff, was convicted of lying to investigators and obstruction of justice following the 2003 leak of the identity of CIA operative Valerie Plame.
President George W Bush later commuted Libby's 30-month prison sentence but did not issue a pardon despite intense pressure from Mr Cheney. No one was ever charged with the leak.
Mr Trump said in a statement that he does not know Libby but "for years I have heard that he has been treated unfairly. Hopefully, this full pardon will help rectify a very sad portion of his life".
The Libby case has been criticised by conservatives, who argue he was the victim of an overly zealous and politically motivated prosecution by a special counsel.
Another twist is that the special counsel, Patrick Fitzgerald, was appointed by James Comey, deputy attorney general at the time. Mr Comey later became head of the FBI but was fired by Mr Trump, and has since written a book highly critical of the president.
White House adviser Kellyanne Conway, while declining at the time to confirm Mr Trump's plans for a pardon, said earlier today that "many people think that Scooter Libby was the victim of a special counsel gone amok". Asked if a pardon would be about Mr Comey, Ms Conway said no.
Ms Plame said a pardon would send a message "that you can commit crimes against national security and you will be pardoned".
The pardon was the third for Mr Trump. He granted one last year for former Arizona sheriff Joe Arpaio, who was awaiting sentencing for contempt of court. Mr Trump also pardoned a US Navy sailor, who was convicted after taking photos of classified portions of a submarine.
Conservative criticism of the special counsel in the Plame case echoes critiques of Robert Mueller, the special counsel leading an investigation into Russian election interference, possible coordination with Trump associates and potential obstruction of justice by the president. Mr Trump has called that probe a "witch hunt."