On January 13, the House of Representatives impeached then-President Donald Trump after his constant lies about the 2020 presidential election prompted a mob of pro-Trump extremists to storm the United States Capitol in a deadly failed insurrection.

At the end of last month, Senator Rand Paul (R-KY) forced a motion that would've declared the Senate impeachment trial of a former President unconstitutional. All but five Republicans voted in favor.

Paul's motion narrowly failed, and on Tuesday, House impeachment managers and Trump's defense team appeared before the Senate to argue whether Senators have the authority to hold an impeachment trial for a President who's no longer in office.

After an argument in the affirmative from lead impeachment manager Jamie Raskin (D-MD) went widely praised, Trump defense lawyer Bruce Castor took the floor, where he proceeded to deliver a 45 minute diatribe that lacked any coherent argument and was riddled with tangents. Trump was reportedly enraged at the ineptitude on display.

Shortly after, the Senate voted 56 to 44 that it had the authority to hold a trial for the former President.

Among the few Republicans who voted in favor was Senator Bill Cassidy (R-LA). Because Cassidy was one of the 45 Republicans who voted for Paul's motion that the Senate impeachment trial of a former President is unconstitutional, his Tuesday vote to proceed with the trial marks a reversal of his earlier position—the only reversal seen among the two votes.

Cassidy's comments on Castor's performance gave some insight as to why the Senator changed his position.

Watch below.

Cassidy told reporters after the vote:

"I said I'd be an impartial juror. ... President Trump's team were disorganized. They did everything they could but to talk about the question at hand, and when they talked about it, they kind of glided over it, almost as if they were embarrassed of their arguments."

He continued:

"If I'm an impartial juror, and one side is doing a great job, and the other side is doing a terrible job, on the issue at hand, as an impartial juror, I'm going to vote for the side that did the good job."

CNN reporter Kaitlan Collins later asked why he thought Trump's defense did a terrible job, to which the Senator responded:

"Did you listen to it? OK then. It speaks for itself."

With that take, even Trump's critics agreed.

Some think Trump's defense is so certain of his acquittal by Republicans that they don't feel the need to put forth a strong effort.

We'll see if Trump's defense revives itself in the remaining days or even weeks of the Senate trial.