Whether a U.S. president can pardon himself has remained an open question in American politics for decades, but it could be answered if former President Trump is convicted of a federal crime and again wins the presidency.

Why it matters: Trump, who currently faces 91 felony counts across four criminal cases, has flirted with using one of the presidency's most powerful abilities to absolve himself of criminal liability in the past.

How do presidential pardons work?

The pardon is among the strongest unitary powers that the president has, as it allows the commander-in-chief to eclipse the federal and military judiciary systems without consulting Congress before doing so.

• It's granted by Article II, Section 2, Clause 1 of the Constitution, which in part states: "he shall have Power to grant Reprieves and Pardons for Offences against the United States, except in Cases of Impeachment."
• It means the president can grant a pardon to anyone convicted of a federal crime in a U.S. District Court, the Superior Court of the D.C. or a military court-martial while using whichever standards he wants.
• He can also commute any sentence imposed by a federal court or the D.C. Superior Court.

While they don't imply innocence, pardons do, in most cases, signify redemption.

• They are generally expressions of executive clemency for people who have accepted responsibility for a crime and have displayed good behavior.
• Thousands of people have received presidential pardons since the beginning of the 20th century, though the rate of clemencies have slowed since the 1960s.

However, though the power of the pardon is immense, it is not absolute.

• A president cannot pardon people convicted of state crimes and cannot commute sentences received for state crimes, which is a power generally reserved for governors, though it differs state by state.
• The founders also ensured that pardons cannot apply to congressional impeachments against federal officials, as that would be a violation of the separation of powers.
• The pardon, too, is constrained only to "Offences against the United States," implying a president can only grant clemency for crimes committed and not future crimes.

Could Trump pardon himself?

The answer is open in part because no president except Trump has ever been charged with a crime.

• But it's also the result of a failure on Congress's part to prohibit the potential practice through a constitutional amendment, though some members of Congress have tried to do so.

Constitutional scholars disagree on whether the president's pardon power extends to himself, and the Constitution and judicial precedent do not resolve the debate.

• Generally, scholars who believe the president can pardon himself have expansive views on executive power and point to the fact that the open-endedness of Article II, Section 2, Clause 1 does not explicitly exclude anyone from receiving a pardon.
• An example is John Yoo, a law professor at Berkeley and former legal adviser in the George W. Bush administration, who argued in a 2017 op-ed that the language does allow a president to pardon himself, but he shouldn't, as it would deeply damage his legitimacy and provoke a political disaster.

On the other hand, scholars who believe a self-pardon would violate the Constitution commonly make etymological arguments about the language in Article II, Section 2, Clause 1 and the intentions of the the framers of the Constitution.

• For example, Frank Bowman, a scholar of constitutional and criminal law at the University of Missouri, has argued that the words "pardon" and "grant" have traditionally implied a two-party exchange, the grantor of the pardon and its grantee, and one person cannot be both.
• Further, he said other actions taken by the framers indicate that they never intended to allow self-pardons and an executive that could not be held to account by the judiciary.
• He pointed to Impeachment Judgment Clause. It in part states that impeachable officials — which includes the president — may "be liable and subject to indictment, trial, judgment and punishment, according to law" if even if they are also subjected to the impeachment process.
• Bowman says this clause, in addition to others, indicates that the framers explicitly meant for the individual occupant of the office of the presidency to be subjected to federal criminal prosecution through the courts and that a self-pardon would erroneously nullify that intention.

The Department of Justice in the past has waded into the debate.

• Just four days before President Nixon resigned, then-Acting Assistant Attorney General Mary Lawton wrote in a memorandum on Aug. 5, 1974 that the president cannot pardon himself because it would violate "the fundamental rule that no one may be a judge in his own case."

What about the state crimes Trump faces?

The presidential pardon does not extend to state crimes, so it's very unlikely Trump could directly affect a conviction or sentence from the charges he currently faces in Georgia and New York.

• But that means there exists a possibility that Trump is found guilty and sentenced for a state crime but still wins election or is found guilty and receives his sentence while in office, both of which would prompt several other legal quandaries.

What has Trump said about a self-pardon?

Trump recently said it's "very unlikely" he would pardon himself if he is convicted of a crime and wins office.

• He's also noted that he already had the opportunity to pardon himself during the final days of his presidency:
• "On the last day, I could have had a pardon done that would have saved me all of these lawyers and all of this — these fake charges, these Biden indictments," Trump said in an interview last year.

But he did defend self-pardons while in office.

• In June 2018, he said in a early morning social media post that he had been told by "numerous legal scholars" that he has "the absolute right" to pardon himself, though he qualified that statement, saying he has no reason to because he's "done nothing wrong."
• At the time, he was under investigation as part of special counsel Robert Mueller's as probe into Russian interference in the 2016 election.
• He also reportedly asked his advisers about whether he could pardon himself or his family if they were charged or convicted as a result of Mueller's investigation.

How has Trump used the power of the pardon?

While in office, Trump did use the power as other presidents had, by, for example, pardoning or commuting the sentences received by people for nonviolent drug offenses or posthumous pardons for historical figures.

• However, unlike many other presidents, Trump issued several pardons or commutations for his political allies, many of whom were convicted of crimes relating to his 2016 presidential campaign.
• Among his allies who received pardons were his former chief strategist Steve Bannon, his former campaign chairman Paul Manafort, his longtime associate Roger Stone and Charles Kushner, the father of his son-in-law, Jared Kushner.
• He also issued extremely controversial pardons for service members and U.S. mercenaries who had been accused or convicted of killing civilians, which is a war crime.

Should a president pardon himself?

Regardless of whether a president can or can't issue a self-pardon, it's worthy to consider if, morally, he should.

• A president pardoning himself in a political climate like today's would likely further inflame the country's partisan divide and exacerbate the public's already deep mistrust in its democratic institutions.
• In other words, in attempting to save himself from criminal prosecution or a sentence through a pardon, a president would deeply damage his legitimacy and could plunge the country into a existential constitutional crisis, potentially igniting political chaos.
• A president who gives himself a pardon also wouldn't completely escape accountability, as he could still be removed from office through the impeachment process.

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