On Sept. 25, Sen. Mitt Romney said, “If the President of the United States asks or presses the leader of a foreign country to carry out an investigation of a political nature that’s troubling … if there were a quid pro quo, that would take it to an entirely more extreme level.”

When he was asked, “Could this rise to an impeachable offense?” Romney replied, let’s “leave it at what I said” and “let the process gather the facts that will ultimately come out.”

So where has the process of fact gathering led us?

We have learned that National Security Council lawyers were so disturbed by the Trump-Zelensky phone call that they had White House officials remove the transcript from the computer system in which such transcripts are typically stored and then loaded it into a standalone computer reserved for codeword-level intelligence information, such as covert action. As the call did not contain anything remotely sensitive from a national security perspective, obviously this was intended to hide its contents from anybody else’s eyes.

Unfortunately Congress and the public are still missing many important facts. President Trump has declined to turn over documents related to the inquiry, and has instructed members of his administration not to testify before Congress.

As a result, key individuals with first-hand knowledge of the affair, including Trump’s lawyer, Rudy Giuliani, Secretary of State Mike Pompeo and Chief of Staff Mick Mulvaney, have ignored subpoenas. The former national security adviser, John Bolton, has also not testified, despite saying that he “was personally involved in” many “relevant meetings and conversations that have not been discussed in the testimonies thus far” and, at one point, declaring that he would have no part in the “drug deal” that Mulvaney and other allies of the president were concocting.

Denying Congress the information it requires raises further concerns about a possible cover-up and obstruction of justice. It makes a mockery of the process by which the congressional branch oversees the executive branch as it considers the solemn question of impeachment. Such behavior simply cannot be tolerated. The rule of law demands that all of the principal witnesses testify. If President Trump is innocent, then he should be happy to have his most senior officials speak about their roles in the Ukraine affair.

The rule of law also demands that all documents relevant to the inquiry are made available without delay. Trump does not have a blanket right to refuse requests for notes, emails or other relevant materials. Even if some of the documents are classified, they can all be shared with cleared members of the intelligence committee. In cases where the president may arguably be able to invoke executive privilege, this should be done only on a case-by-case basis to minimize the risk of cover-up.

In the case of a Senate trial, do our senators really want to sit in judgment of the president based on incomplete information, knowing that the Executive Branch has hidden relevant inputs they would need to do their jobs?

Other than obstruction, the Republican defense has been heavy on banging on the tables, and light on any facts that counter the central narrative surrounding the Trump-Zelensky affair.

Tweets of, “Witch hunt,” “sham investigation” and “kangaroo court” are blatant mischaracterizations of a constitutionally enshrined process to evaluate presidential abuse of office. Trump will almost assuredly be impeached, and no attempts to trivialize these proceedings can take away from the seriousness of investigating whether our president is fit to continue leading our country.

Complaints about process are hollow when the process used, bipartisan closed-door investigations followed by public hearings, are the same as used in the Benghazi investigation and the Clinton impeachment.

It is not persuasive when the whistleblower’s motives are impugned and cries that his identity be revealed, when his motives are irrelevant, as everything he has said has been corroborated by multiple witnesses.

Attempts to slander, ridicule, or intimidate witnesses and potential future whistleblowers fundamentally damage the country’s ability to learn the facts. It follows that Fox News accusing Lt. Colonel Alexander Vindman, a NSC Ukraine expert and veteran with 20 years of military and civilian service, of espionage without factual basis, apparently to discredit him because he fulfilled his duty by reporting his concerns about the Trump-Zelensky conversation, is slanderous and reprehensible.

Trump’s attempt to intimidate former ambassador to Ukraine, Marie Yovanovitch, and other potential witnesses must be loudly and publicly denounced by all congressional members who care about decency and justice. The president simply cannot be allowed to intimidate U.S. government officials from telling the truth about what they know.

In the same vein, we must be wary of any presidential attempts to manipulate witness testimony by dangling pardons in front of those who might be induced to perjure themselves to protect Trump.

While it may be too early for senators to comment on how they view the case or whether the presumed articles of impeachment have merit, our nation cries out for patriotic and eloquent Republican voices that will protect the methodical, multi-dimensional process of fact gathering, the Constitution and the rule of law.

The health of our nation depends on it.

Justin F. Thulin, M.D.

Justin F. Thulin, M.D., is a dermatologist practicing in Salt Lake City.