John Roberts will preside over the impeachment trial of President Trump in the United States Senate. That’s because Roberts is the Chief Justice of the United States. That’s what it says in the Constitution. Not “Chief Justice of the Supreme Court.” He is the Chief Justice of the United States.

The impeachment trial of a president brings together all three branches of the federal government for this solemn process. So solemn that there is a special oath for members of the Senate who (I swear to God) will swear to God that they “will do impartial justice according to the Constitution and laws.”

Mitch McConnell has already told us that he will violate the oath. Actually, violating the oath is itself grounds for impeaching a U.S. Senator. That probably won’t happen. But then, things have gotten extremely weird of late.

The outcome of the trial and of the next presidential election may well depend on whether the Chief Justice chooses to faithfully fulfill his role. If John Roberts truly values our system of laws, if he values our democracy, if he cares about his place in history, he will use his authority to get to the truth.

Article II of the Articles of Impeachment is Obstruction of Congress:

Donald J. Trump has directed the unprecedented, categorical, and indiscriminate defiance of subpoenas issued by the House of Representatives pursuant to its sole power of impeachment.

This is self-evident to a large majority of Americans. In a poll released this week, 71% of Americans want Trump Administration officials like acting White House chief of staff, Mick “Get Used to It” Mulvaney and former national security advisor John “Drug Deal” Bolton to testify during the Senate trial. That number includes 64% of Republicans and 72% of independents!

In yesterday’s House debate, many of the Republican members have claimed (falsely) that there is no firsthand evidence that President Trump shook down President Zelensky to benefit his own re-election. Well…“Read the transcript.” Or read the testimonies of Lt. Colonel Vindman, or Ambassador Sondland, or of David Holmes, who overheard the president through Sondland’s unsecured phone at a restaurant in Kiev. But if any one of those Republicans had ever wanted to learn the actual truth, they would have protested Trump’s blanket denial of Congressional subpoenas.

Republican after Republican repeatedly recycled insanely stupid and dishonest talking points. “The Ukrainians got the aid and didn’t announce an investigation, so there couldn’t have been any conditions.” (Trump released the aid only after Politico had made the story public.)

“If he was being shaken down, Zelensky must be a pathological liar!” (President Zelensky is completely dependent on American aid, so he clearly couldn’t rat on Trump.)

Among the 36% of Republicans who don’t want the president’s men to testify is Mitch “So Help Me God” McConnell. Well, guess what? According to the Senate’s “Rules of Procedure and Practice,” as presiding officer, Chief Justice Roberts “shall direct all forms of the proceedings.” Which means he can make sure that Democrats are able to call for Mulvaney or Bolton or Pompeo to testify.

Yes, McConnell will object. But it takes is a majority to override his objection. That means it will take just four Republicans to say, “Hey, if the President can stop any witness at any time from testifying before Congress, then we’ve fundamentally changed the balance of power that the Founders created.” Collins? McSally? Tillis? Ernst? All running for re-election? How many would defy 64% of Republicans and 72% of independents?

This is in Chief Justice Roberts’ court, so to speak. My feeling is that the Chief Justice cares about the legacy of the Court and about his own place in the history books. So far, he has a mixed record at best. Citizen’s United and Shelby County slanted the playing field in favor of the ultra-wealthy and gave new life to Republican efforts to suppress the minority vote.

But Roberts saved the Affordable Care Act.

Mr. Chief Justice, it’s finally time to really call balls and strikes. The way to determine who’s telling the truth is to stop allowing the President to deny Congress access to documents and witnesses without cause during an impeachment process. The American people will be watching.