Less than a month before the 2016 presidential election, Republican Senators John McCain, Richard Burr and Ted Cruz vowed to block any nominations to the high court made by a potential President Hillary Clinton.

You’ll recall that in 2016, McConnell denied President Barack Obama the chance to have hearings on Judge Merrick Garland, whom Obama tapped to replace the late Justice Antonin Scalia.

McConnell changed Senate procedure with the “nuclear option,” eliminating the filibuster on Supreme Court nominees and changing the number of votes required for confirmation to 51, down from 60.

That left Scalia’s seat unfilled until Trump’s nominee Judge Neil Gorsuch was confirmed to the Supreme Court on April 1, 2017, by a 54-45 vote.

"I promise you we will be united against any Supreme Court nominee that Hillary Clinton, if she were president, would put up," Senator John McCain (R-AZ) said on the Senate floor in October 2016. "I promise you."

Senator Richard Burr (R-NC), who co-chairs the Senate Intelligence Committee, indicated he'd rather see a seat on the bench remain empty than confirm someone appointed by a President Clinton.

If Hillary Clinton becomes president, I am going to do everything I can to make sure that four years from now, we still got an opening on the Supreme Court.

Senator Ted Cruz, the firebrand conservative from Texas, said of the vacancy left by Scalia:

There is certainly historical precedent for a Supreme Court with fewer justices. I would note, just recently, that Justice Breyer observed that the vacancy is not impacting the ability of the court to do its job.

On Wednesday, Justice Anthony Kennedy announced he would be retiring at the end of July after 31 years on the bench, giving Trump another chance to place a young, very conservative judge on the Supreme Court.

McConnell quickly addressed the Senate, saying: "We will vote to confirm Justice Kennedy’s successor this fall."

The Senate stands ready to fulfill its constitutional role by offering advice and consent on President Trump’s nominee to fill this vacancy.

The hypocrisy, and chutzpah, are remarkable.

It is becoming abundantly clear that Republicans would rather game the system in their favor than allow duly elected Democratic presidents to do their jobs.

Of course, McConnell and his fellow Republicans in the Senate have no intention to delay hearings on Trump's Supreme Court pick until after November's midterms, despite the majority leader's own standard that the American people should be able to vote first.

“The American people are perfectly capable of having their say on this issue, so let’s give them a voice. Let’s let the American people decide. The Senate will appropriately revisit the matter when it considers the qualifications of the nominee the next president nominates, whoever that might be,” McConnell said in 2016.

“One of my proudest moments was when I told Obama, ‘You will not fill this Supreme Court vacancy,'” McConnell said in 2016.

In 2017, he said:

Apparently there’s yet a new standard now, which is not to confirm a Supreme Court nominee at all. I think that’s something the American people simply will not tolerate.

Meanwhile, Trump is under federal criminal investigation for possibly conspiring with a hostile foreign power to steal the 2016 election - and now has an opportunity to choose a new member of the Supreme Court, which may ultimately decide his and the fate of Special Counsel Robert Mueller's investigation.

On Thursday, John Marshall of Talking Points Memo cited a former federal public corruption prosecutor, who wrote to him: "this is DEFCON 1 for the rule of law in this country."

A President under federal criminal investigation for stealing an election should not be able to nominate the person who may decide his fate. There will be a cloud over the legitimacy of this nomination unless and until the cloud of the Mueller investigation has been lifted.