Here is the self-inflicted blunder Mitch McConnell made that destroyed his entire case: ex-DOJ official

The former chief of the criminal fraud section at the Department of Justice broke down a mistake made by Sen. Majority Leader Mitch McConnell (R-KY) late on Tuesday evening.

McConnell urged something known as "vote stacking" in which there would be a vote-a-rama sequence of vote after vote -- without any debate on the amendments.

Andrew Weissmann, who played a management role in special counsel Robert Mueller's investigation, explained how McConnell undermined his own argument.

"I think Mitch McConnell may have made a bit of a miscalculation there because what he is really saying -- 'Can you stack these?' -- is it doesn't matter what you say, because we're going to vote against it," he explained.

"That is remarkable," Weissmann said. "This is supposed to be about the facts and the law and you have the Democrats, whether you agree or not, they are making individualized assessments of each of the requests they've made. Why is it that we need OMB? Why is it we need the State Department? To turn to the Democrats and say, 'Hey, can you just put this all together? Because it doesn't matter.' That is a really bad signal."

Watch: