(CBSDFW.COM) – Six Republicans joined Democrats in the U.S. Senate in voting the impeachment trial against former President Donald Trump is constitutional and should move forward.

Both of Texas’ Senators, John Cornyn and Ted Cruz agreed with most in the GOP and the former President’s lawyers that the trial should not proceed because Mr. Trump is now a private citizen.

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It’s the first time a former President is facing an impeachment trial and a second time for Mr. Trump.

Lynne Rambo, Professor Emerita of Constitutional Law at Texas A&M University, said she believes the trial is constitutional.

“There’s not really any question that it’s constitutional for them to move forward. Not only is there nothing in the constitution prohibiting it, there are two outcomes of a conviction.”

While the first outcome, removing him from office, is no longer an issue, Senators would need to convict the former President before reaching the second outcome of preventing him from running for President or any federal office again.

The Constitution sets a high bar to convict a President.

More than two-thirds of the Senate, 67 members, would need to vote to approve.

Republicans have already said that’s not going to happen and that they expect he will be acquitted for a second time.

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Rambo said, “I do think that the two thirds requirement of conviction in the Senate is a very, very big impediment to charges being brought.”

When asked if that requirement should make House members think twice about impeachment, Rambo said, “That’s a terrific question. I think it should certainly make them think twice. But at the end of the day, I think you have to do what’s right, from an ethical and public service standpoint.”

The House impeached the former President for incitement of insurrection, saying his speech January 6th led to the deadly riot at the Capitol hours later.

Prosecutors have revealed in court documents that some of the people charged with violently entering the Capitol planned to do so before the speech that day.

Rambo said the evidence is still being gathered in terms of what was planned and what was being said before-hand. “What was communicated back and forth in various camps, including the President’s. So I don’t know that I think that they’re planning it particularly lets him off the hook to the extent that he joins in and further insights it, but that’s an interesting perspective on it.”

Democratic Senator Patrick Leahy is presiding over the trial after Chief Justice John Roberts decided against it without a public explanation.

The trial is expected to last about a week.

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