“This impeachment is not only an attempt to undo the last election — it is an attempt to influence the next one too,” House Minority Leader Kevin McCarthy, R-California, argued last week during the debate over the impeachment of President Donald Trump. And he closed by calling on Democrats to let the American people “choose the next leader of the free world. Follow the principles of our Constitution.”

But by invoking the 2016 election in the same breath as the upcoming 2020 election, McCarthy leaves no window for Congress to consider the impeachment of any president. And to imagine the nation’s founders unknowingly nullified the most important constitutional check on presidential power is absurd.

McCarthy’s argument was pulled from the letter Trump’s attorney sent to Congress in early October. That also stated the administration wouldn’t comply with initial impeachment inquiry in part because it lacked “the necessary authorization for a valid impeachment.”

But when Democrats finally relented and held a vote to formally authorize it, every single Republican opposed it. The White House is still calling it illegitimate, refusing to comply congressional subpoenas and directing witnesses not to testify. That means Democrats will likely add obstruction to articles of impeachment sent to the Senate.

Here again the Constitution is clear this isn’t a matter for the voters to decide. It explicitly assigns members of the U.S. Senate to be the jury that ultimately determines whether an elected president should be removed from office.

Among the upper chamber’s Republicans, Sen. Lisa Murkowski, R-Alaska, is one of the few who understand the constitutional duty to refrain from judging the case before the House completes its inquiry. Only after they vote to impeach should they consider the evidence presented, deliberate on the charges, and reach their verdict.

Murkowski had criticized the initial House impeachment proceedings. But she was one of two who didn’t endorse a resolution condemning it.

“A serious lack of transparency will hardly build public trust or credibility for the House’s actions,” she warned. But she went on. “As awful as their process is, the formal impeachment inquiry lies in the House, and it’s not the Senate’s role to dictate to the House how to determine their own rules.”

That was a few days before the House vote formalized the inquiry and established the process for public testimony and questioning of witnesses by committee members. Now Murkowski should issue to a warning her own party. Continuing to undermine the legitimacy of the inquiry equates to aiding and abetting presidential obstruction of justice.

Every senator knows they can’t possibly render an unbiased, informed verdict unless they’re given a full accounting of the administration’s actions on the Ukrainian controversy. Without it, the outcome of the Senate trial will be no better than if Americans tuned in to Rachel Maddow or Sean Hannity for the verdict they want to hear.

As Emma Green wrote in The Atlantic last week, “one outcome seems sure: This bitter fight will make it even harder for Americans to see their political opponents as reasonable humans. Instead, impeachment may end up serving as one more guidepost, pointing Republicans and Democrats to their respective sides.”

The hostility will be inflamed by one unresolved question: was this impeachment constitutionally valid?

A Supreme Court ruling may be the only way to definitively answer that.

Back in April, Trump tweeted if Democrats “ever tried to Impeach, I would first head to the U.S. Supreme Court.” Since then, House Democrats filed two unrelated lawsuits challenging Trump’s refusal to comply with congressional subpoenas. Both are expected to head to highest court as well.

This case should supersede those and be scheduled for an expedited review by the court. Based on past precedents, it seems unlikely they’d intervene on the rules established for the inquiry. But if the court were to stand aside while Trump impedes a thorough investigation by Congress, then the power to impeach may just as well be removed from the Constitution.

I don’t believe constitutional conservatives like Justices Neil Gorsuch and Brett Kavanaugh would stand for that. If they were to join the majority and rule against the president who nominated them, then Americans would know impeaching Trump was legitimate. And more senators might reach a verdict based on the facts instead of partisan loyalties.

• Rich Moniak is a Juneau resident and retired civil engineer with more than 25 years of experience working in the public sector. Columns, My Turns and Letters to the Editor represent the view of the author, not the view of the Juneau Empire.