Free elections and what Americans know as the rule of law are core principles of a constitutional democracy. It is hard to imagine more serious threats to our 200-year-old form of government than the flagrant violation of either safeguard. Yet, those are the allegations that form the basis of the impeachment proceedings against the President.

The GOP leadership in Congress has shown little interest in learning whether the accusations have merit, and have voiced even less concern for whether mortal wounds are being inflicted on the rule of law — the bedrock principle that says all persons and institutions are accountable, and that the exercise of power is subordinate to established law. The initial inquiry was straightforward: Did Mr. Trump invite foreign interference in the nation’s free election process by secretly withholding authorized foreign military aid until a vulnerable foreign leader made announcements advantageous for Mr. Trump’s re-election chances? If so, did that attempted election interference constitute an abuse of the powers of the presidency? Then, after a whistleblower’s complaint exposed what had happened, did Mr. Trump engage in an attempted cover-up, using means that sought to place himself above the law? If true, these misuses of presidential power — seeking to manipulate the free election process and obstructing legitimate inquiry — violate the most basic understanding of the rule of law. That is, the use of high office in a manner that avoids accountability and seeks to place oneself above the law. We can only imagine what might have happened if the whistleblower had not come forward, or if the foreign power later attempted to use a President’s unlawful secret conduct in a way against America’s best interests.

During the House of Representatives inquiry, Mr. Trump withheld evidence, and ordered executive branch officials to neither produce documents or testify. The giving of these instructions is not in dispute. Rather, Mr. Trump asserted that his defiant conduct was a proper exercise of his presidential powers. As constitutional scholars quickly pointed out, the implication of the assertion was breathtaking: A president who cannot be investigated has placed himself above the law, thereby nullifying our nation’s adherence to the rule of law.

Once the House inquiry concluded, without hearing from key executive branch officials, the GOP membership of the Senate closed ranks. Without any real explanation, they have taken the position that whatever the entire facts, the outcome of an impeachment trial will be the same. Two of the most important voices, Majority Leader Mitch McConnell and Senator Lindsay Graham (R-S. Car.) — both law school trained — have publicly displayed explanatory contortions almost too painful to watch. They contend that a “trial” as required by the Constitution doesn’t mean a real trial where all the relevant testimony and evidence is presented. With a straight face they say that persons like former national security adviser John Bolton and chief of staff Mick Mulvaney, both instructed by Mr. Trump not to testify in the House proceedings, are now prevented from testifying because their testimony was not first presented to the House. As trial lawyers know, there can be only one rational explanation for their bizarre posturing: They have something to hide. The full facts, if disclosed, would not be good. By seeking to prevent evidence through procedural gamesmanship, they have chosen allegiance to Mr. Trump over responsible leadership. At first, Mr. Graham had hopefully indicated respect for his public servant obligations. He told the nation that if there was any evidence of “quid pro quo” it needed to be heard. Now he has retreated from seeking truth to the shadows of disingenuity.

Most appalling, both Mr. McConnell and Mr. Graham have promised that any future “trial” proceedings will be over quickly, followed by Mr. Trump’s full acquittal. Mr. McConnell has stated his commitment to “total coordination” with Mr. Trump in defending the underlying allegations. The public promises of Messrs. McConnell and Graham blatantly ignore their future Senatorial juror oaths to render “impartial justice.” At best, their pretrial pronouncements of Mr. Trump’s full innocence trash the rule of law’s commitment to blind, impartial justice and the assurance that no person or institution shall be above the law. Their corrosive amnesia of what they once knew as law-trained public servants is sad to watch. Their maneuvering seeks to take our constitutional democracy to a new place — a place that dishonors the need to safeguard free elections and allows our highest institution to function above the rule of law.

And so, while the nation readies itself for what portends to be a rigged proceeding, Mr. Trump and his defenders ramp up their heated rhetoric, complaining it’s all a “witch hunt” to steal away Mr. Trump’s 2016 election; that no factual evidence supports the allegations; and, that, regardless of whatever happened between Mr. Trump and the Ukrainian President, that exchange could never constitute grounds for impeachment. If all goes as the President’s defenders forecast, add the rule of law to the long list of wounds caused by the Trump presidency.

Don Holladay is a retired attorney whose background includes constitutional litigation.

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