We pause to ponder that particularly powerful presidential prerogative, the pardon. (Please pardon our P’s.)

President Trump’s pardon-palooza — with writs of forgiveness flying out of the West Wing like souvenir pens — is only the latest controversy stirred by one of the U.S. Constitution’s most sweeping clauses: “The President … shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment.”

Not all the Founding Fathers loved the idea of giving the new nation’s chief executive such kingly authority to overturn the verdict of juries and the judgment of judges. They would have been floored to hear Trump’s attorney, Rudy Giuliani, argue Sunday that the president probably has the power to pardon himself.

On Monday, Trump went a step further, tweeting that “I have the absolute right to PARDON myself, but why would I do that when I have done nothing wrong?”

Legal scholars disagree about whether Trump’s claim is true. And no president has ever tried to pardon himself.

It certainly wasn’t contemplated by the Founding Fathers as they debated giving presidents the same power to pardon as British monarchs. Boosters of a strong central government argued that allowing presidents to grant forgiveness, particularly in cases of rebellion, could spread peace and love through the restless young republic.

“A well timed offer of pardon to the insurgents or rebels may restore the tranquility of the commonwealth,” wrote Alexander Hamilton in the Federalist Papers.

Sure enough, our first president employed the first pardon after the first major uprising, the “Whiskey Rebellion,” a violent revolt against a tax that Hamilton himself had imposed. George Washington pardoned the two men convicted of treason, sparing their lives, clearing their records and leaving the duty on hooch intact.

The presidential superpower includes full pardons (effectively eliminating the existence of the conviction) and clemency/commutations (freeing the convict early from his or her sentence or probation). Washington exercised the prerogative a judicious 16 times, 12 of them on a single day, according to the informative Pardon Power blog maintained by political scientist P.S. Ruckman Jr.

The pardon pace barely quickened under John Adams (21) but surged under the third president, Thomas Jefferson, who granted it to 119 citizens. Among them was David Brown, a New England firebrand imprisoned under the infamous Alien and Sedition Acts of 1798 that made it a crime to criticize the federal government.

A few decades later, on Christmas Day in 1868, the biggest class of rebels against the United States ever got a presidential pass when Andrew Johnson granted “every person who, directly or indirectly, participated in the late insurrection or rebellion a full pardon and amnesty for the offense of treason against the United States.”

Johnson also officially forgave Lincoln conspirator Samuel Mudd, reasoning that his treatment of John Wilkes Booth was probably more about medical duty than complicity in the assassination.

By many interpretations, Confederate leaders Jefferson Davis and Robert E. Lee were left out of the post-Civil War pardon pushes of Johnson and his successor Ulysses S. Grant. Their modified pardons came much later when Gerald Ford signed an act of Congress restoring Lee’s full citizenship rights, and Jimmy Carter approved one making Davis wholly American 97 years after his death.

Carter also issued a sweeping all-is-forgiven for Vietnam War draft resisters. And because the pardon power had long expanded beyond cases of treason or rebellion, he also pardoned Watergate-era convict G. Gordon Liddy and folk singer Peter Yarrow.

James Madison had the distinction of officially forgiving the first spy, a Brit captured in New York, and one of the first pirates, the dashing New Orleans-based buccaneer Jean Lafitte.

Two centuries later, Barack Obama resisted pleas for forgiveness for another high-seas raider, Abduwali Muse, one of the Somali pirates convicted of capturing the cargo ship Maersk Alabama, as seen in the 2013 film “Captain Phillips.”

By this time, the parade of pardons had become vastly more populated. Obama granted official mercy to 1,927, and that was down from Franklin Roosevelt’s (the longest-serving president) whopping 3,687 pardons and commutations.

Richard Nixon is the only president to have both issued pardons and received one (from his successor, Gerald Ford). Lewis “Scooter” Libby is among a select group of the convicted to win tag-team mercy from two presidents: George W. Bush commuted Libby’s prison term for his role in outing a CIA agent, and Trump bumped it to a full pardon last month. Another is Patty Hearst, the wealthy kidnap victim-turned-bank robber: commuted by Carter, pardoned by Bill Clinton.

Clinton also pardoned his brother, Roger Clinton, after he served time for cocaine possession. Then, just hours before leaving office, Clinton granted fugitive financier Marc Rich a pardon — a decision that caused outrage and led to federal investigations.

Ronald Reagan pardoned New York Yankees owner George Steinbrenner after he pleaded guilty to illegally contributing to Nixon’s campaign. Nixon commuted the sentence of Jimmy Hoffa after the Teamsters leader started his sentence for jury tampering.

And the clemency carousel goes round. At press time, Trump had added six names to the list of those touched by the pardon pen, from former Arizona sheriff and immigration hard-liner Joe Arpaio to conservative commentator/conspiracist Dinesh D’Souza. Where he will point it next?  Martha Stewart wants to know.

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