Lewis “Scooter” Libby
Who pardoned him: George W. Bush, Donald Trump
What he was pardoned for: Perjury and obstruction
Why it was controversial: A CIA operative, Valerie Plame, had her identity revealed. Though Libby was not accused of being the leak, he was accused of perjuring himself during the investigation of the leak, and obstructing the investigation. Many felt that in pardoning Libby, Bush was abusing his power to protect the government from oversight into a grave incident that threatened lives and national security.