The power of a president to pardon people for crimes has always been controversial. Some early American leaders thought it smacked too much of royalty.
But Alexander Hamilton argued the law should have avenues for mercy, or "justice would wear a countenance too sanguinary and cruel." He thought one person was more likely to use such power with conscience than a committee.
The history of presidential pardons is often surprising. George Washington pardoned two men who led the Whiskey Rebellion. He didn't condone a tax collector being tarred-and-feathered, but thought the men responsible should not be hung for treason.
President Millard Fillmore pardoned the two white captains of The Pearl, a schooner that tried to help 77 enslaved people escape to freedom. But most of the Black people on the ship were sold back into slavery. President Abraham Lincoln pardoned 265 members of the Dakota Tribe for their roles in the Great Sioux Uprising of 1862. But he allowed dozens more to be hanged, after what historians agree were unconvincing trials. On Christmas Day of 1868, President Andrew Johnson offered pardons to everyone who fought for the Confederacy.