The use of the autopen, a device that reproduces signatures and is ubiquitous in government and business, is ordinarily uncontroversial. There is no power to undo a pardon in the Constitution or case law.

A 2005 memo from the Justice Department, issued during George W. Bush’s presidency, said that using an autopen to sign official documents is legal, and the practice is now widely used.

President Donald Trump signaled that he intends to nullify the presidential pardons—issued to those on the House Jan. 6 committee that investigated Trump—executed by President Joe Biden because, he said,