Ukraine scandal: I know why Trump top dogs — Mulvaney, Pompeo, Perry & Bolton — won't bark Because it would be so easy for these people to clear the president, it’s hard to escape the conclusion that their silence is part of a cover-up.

Angus King | Opinion contributor

Show Caption Hide Caption Trump's Ukraine phone call: U.S. and Ukraine relationship, explained U.S. and Ukraine relations go further back than the now infamous phone call between Trump and Zelensky. We explain their relationship.

One of Sherlock Holmes’ most famous cases was solved when a normally noisy dog was silent the night of the crime, leading the famous detective to the deduction that it must have been an inside job — the dog knew the intruder.

Those not barking today are the numerous Trump administration officials who are strangely silent when a few short statements (under oath) could go a long way toward exonerating the president from the charge of using the powers of his office for personal gain.

Acting chief of staff Mick Mulvaney, Secretary of State Mike Pompeo, Energy Secretary Rick Perry, former national security adviser John Bolton and probably at least a dozen White House and National Security Council staffers — all could clear up, one way or another, the essential question of whether the president was interested in corruption generally in Ukraine last summer, or whether the withholding of military aid and the dangling of a White House meeting was motivated by his personal and political interest in publicized investigations of the 2016 election and the activities of one of his principal rivals. And this would be direct evidence, which no one can call hearsay.

Because it would be so easy for these people to clear the president, it’s hard to escape the conclusion that their silence is less about vague assertions of executive privilege (which isn’t available to cover-up wrongdoing, in any case) and more about not wanting to testify under oath as to what actually happened.

Trump innocence proclaimed

The president continuously proclaims his innocence (the call with the president of Ukraine was “perfect”, the impeachment proceedings are a “hoax,” a “witch hunt” and a relitigation of the 2016 election), which is his right. What is not his right is the active obstruction of the fact-finding process by blocking the testimony of useful witnesses as well as directly (and through his surrogates) attempting to intimidate those who have come forward.

I know of no legal proceeding in any forum where the alleged wrongdoer controls the availability of material witnesses. In most situations, in fact, the very attempt to do so is a crime in itself. If the president is innocent, he should want — no, he should demand — that the above mentioned officials appear in a public forum, under oath and subject to examination, to set the matter straight, as soon as possible.

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Indeed, Donald Trump's White House blocks witnesses from coming forward even as he publicly tweets that he'd like them to testify. He can and should rescind his administration's orders today.

Let Ukraine facts out

It’s likely that the full story of this episode will eventually come out (Bolton is reportedly already working on a book, for example). If I were one of the president’s advocates, I would rather have all the facts now rather than have to explain my vote in light of “new” but currently available evidence.

It is not too late for these witnesses to come forward; the process is still ongoing. As a potential juror, my ultimate judgement will be based on the facts as presented, but also, at least in part, upon whether we have this important testimony — and if we don’t, whether it was withheld from us deliberately.

As we learned from Holmes, silence can sometimes be the most powerful evidence of all. Elementary.

Sen. Angus King, an independent senator from Maine, serves on the Select Committee on Intelligence and the Armed Services Committee. Follow him on Twitter @SenAngusKing