In his immortal 1963 “Letter from a Birmingham Jail,” Martin Luther King Jr. responded to a cadre of southern clergy which had publicly chastised him for organizing demonstrations that were likely to lead to more violence.

Drawing on the thinking of St. Thomas Aquinas, King famously countered that the moral law stands above human law and that when the latter (segregation in that case) contradicts the former, we have a moral duty to disobey the human law.

This distinction between the moral and political realm applies to the heated debate about whether Congress should begin an impeachment inquiry against President Donald Trump.

Our representatives, no less than our president, swore an oath to protect and defend the Constitution. This moral duty to “protect and defend” demands impeaching a president, or any other public official, “guilty of treason, bribery, or other high crimes and misdemeanors.”

While the framers did not exactly state what they meant by “high crimes and misdemeanors,” Republican Congressman Justin Amash of Michigan, a strong advocate for impeachment, is right to read high crimes and misdemeanors as actions violating the public trust.

Conservative pundit George Will is dismissive about the possibility of a Trump impeachment. However, he was not shy about specifying what he took to be grounds for impeachment. According to Will, when it comes to overturning the will of the people, a president should face impeachment on either or both of two counts: wrongs done in the past or wrongs likely to be done in the future.

As for past wrongs, forgive me for reciting a litany that you probably have heard 100 times, but after a two-year investigation, Special Counsel Robert Mueller registered at least 10 instances of Trump attempting to obstruct justice. These efforts ranged from dangling pardons to trying to fire Mueller to the president instructing his lawyer to create a false internal narrative that denied that Trump ever sought to have the special counsel dismissed.

As for possible future wrongs, considering the heartless separations of asylum-seeking parents from their children at the border, threats and retracted threats of tariffs, trusting our adversaries over our own intelligence, telling his minions to refuse to answer questions from Congress, creating a rift with our allies, mistruths as numerous as the stars, crude and scurrilous tweets, and a nonchalant attitude toward Russian interference in our election, it is evident that the self-described “stable genius” has the capacity to drive our country off the cliff.

As of June 22, more than 70 Democrats had signed on to press for an impeachment inquiry, but Speaker of the House Nancy Pelosi and other Democrats believe a blizzard in the Bahamas is more likely than Senate Republicans voting to oust the president.

More than that, Pelosi is standing her ground against impeachment hearings for fear that an absolved Trump would use his absolution as an effective weapon in the 2020 election.

But there are more fundamental moral questions lurking behind the impeachment debate: Do our representatives have a moral duty to begin an impeachment inquiry, no matter what? Or are Pelosi and company right in thinking that the moral obligation is to do whatever produces the best consequences, namely ridding ourselves of would-be emperor Trump?

After carefully studying the Mueller report, Rep. Amash tweeted, “The ball is in our Congress.” In other words, come what may, Congress must uphold the law of the land and begin an inquiry. From the congressman's perspective, a duty is a duty is a duty.

As Amash, Sen. Elizabeth Warren, and others seem to believe the Constitution does not prescribe that a president who commits high crimes and misdemeanors ought to be tried for impeachment, unless so doing might increase the likelihood of the accused remaining in office. Nor does it say, “Go ahead with impeachment proceedings unless doing so might prompt a difficult primary challenge,” which, by the way, Donald Trump Jr. already has promised for Amash.

It says, instead, no one is above the law.

Gordon Marino is a professor of philosophy at St. Olaf College in Northfield, Minn., and is the author of the 2018 book, “The Existentialist’s Survival Guide.” He wrote this for the News Tribune.