Senate Majority Leader Mitch McConnell will not call the Democrats’ four wished-for impeachment witnesses during President Trump’s impeachment trial. And he is under no obligation to do so.

Minority Leader Chuck Schumer handed McConnell a list of names the Democrats would like to hear from, specifically acting chief of staff Mick Mulvaney, former national security adviser John Bolton, senior Mulvaney adviser Robert Blair, and Office of Management and Budget official Michael Duffey.

McConnell called it a “strange request” and said it is not the Senate’s responsibility to “do House Democrats’ homework for them.” Granted, House Democrats did try to hear from these witnesses, but the White House blocked their requests. In McConnell's view, they should have waited for the courts to decide on whether they had to testify.

There’s an argument that preventing Mulvaney, Bolton, and the rest from testifying is a disservice to the truth. My colleague Quin Hillyer makes it here. These officials likely know more about Trump’s dealings with Ukraine than any other official we’ve heard from, and their testimonies could provide much-needed clarity.

But it isn't McConnell’s job to provide clarity. It’s to stand with and lead his party — the president’s party. That means McConnell’s immediate responsibility as Senate majority leader is to deal with impeachment quickly.

McConnell is well within his rights to deny the Democrats’ requests. The rules of impeachment, although they can be changed at any time by a simple majority, do not require witness testimony. And on a more basic level, the Senate’s role in the impeachment process is not to investigate, as McConnell said this week, but to act as “judge and jury, to hear a trial,” deliberate, and then vote.

Democrats have argued that McConnell must allow these White House officials to testify. They are factually wrong. No such requirement exists. Besides, no amount of witness testimony will change the result of the Senate’s trial. Trump will almost certainly be acquitted, and any delay is, at this point, a waste of time.