Editor’s Note: John Avlon is a CNN senior political analyst. The views expressed in this commentary belong to the author. View more opinions at CNN.

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The Founding Fathers would have been disgusted by President Donald Trump’s serial abuse of the pardon power. Nearly 90% of his pardons to date have gone to friends or politically connected allies – including corrupt politicians. While the President’s pardon power may seem unconstrained by the Constitution, a closer look shows that Trump is violating every principle the framers of the Constitution assumed would be followed by a principled President – and there’s evidence they intended special constraints on a President’s pardon power after they’d been impeached.

John Avlon, CNN

Remember, the Founders were focused on restraining the power of the President to ensure he would not turn into a new type of tyrant. That’s why the President’s pardoning power was so hotly debated at the constitutional convention.

Virginia’s George Mason argued that the President “ought not to have the power of pardoning, because he may frequently pardon crimes which were advised by himself… If he has the power of granting pardons before indictment, or conviction, may he not stop inquiry and prevent detection?” Mason warned that this could “destroy the republic.”

But wait, some will say, the Founders did not ultimately enshrine Mason’s warning into the Constitution’s broad final language: “power to grant reprieves and pardons for offenses against the United States, except in cases of impeachment.”

In response, I’ll raise you President James Madison and Alexander Hamilton.

Madison argued that a President’s pardoning power would be restricted during the impeachment process – precisely the situation Donald Trump finds himself in today. As the Brookings Institution’s D.W. Buffa explains, “What can stop him pardoning anyone who was involved in the crimes for which the president is being impeached or whose testimony might put him in jeopardy? The president, according to Madison, still holds office, but he no longer has the power to pardon. The House can ‘suspend him when suspected, and the power will devolve on the Vice-President. Should he be suspected, also, he may likewise be suspended till he be impeached and removed, and the legislature may make a temporary appointment. This is a great security.’”

Hamilton, likewise, believed that Presidents’ broad pardoning powers did not mean they would operate without ethical constraints. In Federalist 74, Hamilton discussed the debate over presidential pardons at length – and made it clear that he assumed the President, then expected to be George Washington, would be a “man of prudence and good sense.” This is unfortunately not the case with Trump.

Hamilton also assumed that pardons would be used to address an injustice, at a time when many crimes were punishable by death. As a result, he reasoned that checks and balances on the President’s pardoning power – such as advice and consent from Congress – could result in a literally deadly delay that would deny justice forever.

When the now timely subject of sedition or treason were raised as extreme examples for presidential pardon power, Hamilton argued that “in seasons of insurrection or rebellion, there are often critical moments, when a well-timed offer of pardon to the insurgents or rebels may restore the tranquility of the commonwealth; and which, if suffered to pass unimproved, it may never be possible afterwards to recall.”

In this, Hamilton perfectly anticipated the scenario when President Washington offered a pardon for charges of treason brought against the instigators of the Whiskey Rebellion less than a decade later. Mercy secured the public good.

But if President Trump offers a broad pardon or amnesty to his supporters who stormed the US Capitol in an attempted coup on January 6, the prospect of a general pardon would be to reward his supporters for an attack on the government – not to secure the common good. This is the opposite of what the Founders intended.

Which brings us to the final insult: the idea that a President can pardon himself. This is absurd on its face “under the fundamental rule that no one may be a judge in his own case, the president cannot pardon himself.” That was the principle cited by a 1974 Office of Legal Counsel opinion during President Richard Nixon’s politically fatal travails with Watergate. Advocates of the unitary executive might come up with other arguments, but the undeniable logic of the principle still stands. The alternative would put the President above the law and give him the power to legally excuse any tyrannical action he took in office. This was clearly not what the Founders intended.

And for what it’s worth, the President’s lawyer, Rudy Giuliani, argued on NBC’s “Meet the Press” in 2018 that “the President of the United States pardoning himself would just be unthinkable. And it would lead to probably an immediate impeachment.”

Speaking of impeachment, it’s clear that the Founders’ assumption that impeachment would be a constraint against abuse of the pardon power was imperfectly thought out. They did not adequately appreciate that Presidents would issue their most controversial pardons on their way out the door, making the prospect of impeachment less of a deterrent to this abuse of power.

In any case, there are a few constraints in place. No pardon can protect a person from prosecution for future crimes. There is no permanent get out of jail free card. Moreover, presidential pardons do not restrict state and local prosecution, which Trump has every reason to fear.

The Founders’ intent also makes a strong case that pardons for people who may have committed a crime at the order of a President or blanket pre-emptive pardons to family members and political cronies ought to be rejected by any judge who calls themselves an originalist. (For a deeper dive into this argument, I recommend reading Professor Aaron Rappaport in Just Security).

Regardless, there clearly is a need for reform of the President’s pardoning power – even if it is to formalize past democratic norms, like the Justice Department signing off on recommendations, which should be based on clemency, not cronyism.

When President Bill Clinton bypassed regular Justice Department channels to pardon financier Marc Rich, there was resounding and repeated outcry from conservative editorial boards – the Wall Street Journal, in particular. But they have been largely silent about Trump’s corrupt abuse of the pardoning power to date. Notably, a then-Senator named Joe Biden was quoted in a February 13, 2001 WSJ editorial as saying it was “totally indefensible.”

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    This kind of moral consistency across partisan lines is rare (though GOP Sen. Ben Sasse accurately slammed the pardon of Paul Manafort as “rotten to the core.”). But the investigations that followed Clinton’s dodgiest pardons should certainly be pursued in Trump’s case.

    The purpose of the pardon is to do justice, not to excuse injustice. Donald Trump, characteristically, seems hell-bent on doing the opposite – to benefit himself. And more sordid pardons on his way out of the White House will only solidify his reputation as the worst and most corrupt President in American history.