Harvard Law professor emeritus Alan Dershowitz warned that former Attorney General Bill Barr is "dead wrong" on his assessment of the latest Trump indictment, arguing prosecutors will have to prove the former president knew and believed he lost the 2020 presidential election to prevail. Dershowitz joined "The Brian Kilmeade Show" on Thursday to discuss his previous legal predictions and why the Justice Department could be facing an uphill battle in proving Trump's alleged guilt in connection with the Jan. 6 charges. 

TRUMP INDICTED ON CHARGES OUT OF SPECIAL COUNSEL PROBE INTO JAN 6

ALAN DERSHOWITZ: I predicted all four of the indictments. And I also predicted that the Hunter Biden plea bargain would not be accepted. The reason my predictions are correct and CNN's are always wrong is they're always wishful thinking. And mine is just based on my experience. I don't have a horse in the race. I just try to predict based on 60 years of doing this. But the main point of principle that I really want to get over is that, and this applies to both parties, the leading candidate against the incumbent president should never be prosecuted by the attorney general of the president, of course, unless the case against him is overwhelming and beyond any dispute. The Nixon standard is what I call it, that it's so overwhelming that both parties support it. That didn't happen in this third indictment. It's not going to happen in the fourth indictment. It didn't happen in the first New York indictment. It may have happened in the Florida indictment with that one piece of evidence of the president foolishly waiving a piece of classified material in front of a writer and the publisher and saying, 'I could have declassified this when I was president, but I didn't.' But the crime there isn't particularly serious. It's the paper technical crime. So I just don't think that they have it enough against this candidate who's now running 44 to 44 in the New York Times poll to use the criminal justice system to interfere with the election. 

Bill Barr, Trump's attorney general from 2019-2020, told Fox News Digital, "I do not support Trump for the GOP nomination and will not be endorsing him." (Michael Reynolds-Pool)

I like Bill Barr. He's a good man, but I think he's just dead wrong about that. Of course, this is a free speech case. Everything involves his exercise of free speech and not only First Amendment free speech, but also the First Amendment right to petition the government for redress of grievances. The way you protest an election is to come up with an alternate slate of electors. That was done in 1960. That was the Tilden Hayes election. That's been done throughout history. And a court in Hawaii said that's the right way to do it. You know, it's interesting that the indictment is based on lies, and the indictment itself contains a blatant lie by Jack Smith. He describes the speech of January 6, a speech that I think was terrible, never should have been made. But he describes the speech in the indictment and deliberately and willfully leaves out the keywords of the speech, namely that the president told his people to protest peacefully and patriotically. By leaving out those words, it's a lie by omission. 

Former President Donald Trump, left, and Special Counsel Jack Smith. (Getty Images)

And under the standards set out in the indictment, you know, Jack Smith could be indicted. He could also be indicted, theoretically. It's not going to happen, obviously. … The Ku Klux Klan statute that says any people who conspire to deny somebody their constitutional rights is guilty of a crime. What if the Supreme Court ultimately rules, as distinguished from what Barr said, that everything that Trump did and said is protected by the First Amendment? That would mean that Jack Smith tried to deny Trump his constitutional rights in this indictment. I make that point not to argue that Jack Smith should be indicted. To make the point that the indictment is so broad, so wide, so all encompassing, it could include so much political conduct. You know, we have two presidents in our history. Of all of our presidents, only two have been called honest — Honest Abe, and Washington and the cherry tree. Does that mean that every other president has been dishonest? Probably. Probably every single one of them has told a fib to get elected or to stay in office, and we don't punish. We don't criminalize political lies, and the government is going to have to prove beyond a reasonable doubt that Trump himself knew and believed that he had lost the election. I don't think anybody who knows Trump thinks that that's true. Trump talked himself into believing that he had won the election, and if that's the case, then there's no corrupt motive or intent.

SPECIAL COUNSEL JACK SMITH SAYS JAN 6 ‘FUELED BY LIES’ FROM TRUMP, PRAISES ‘HEROES’ WHO DEFENDED CAPITOL

In this Jan. 6, 2021, file photo with the White House in the background, President Donald Trump speaks at a rally in Washington, D.C. (AP Photo/Jacquelyn Martin, File)

Former President Donald Trump is scheduled to appear in federal court in Washington, D.C., on Thursday afternoon after being indicted on charges that stem from Special Counsel Jack Smith’s investigation into 2020 election interference and the Capitol riot on Jan. 6, 2021.

Trump, the 2024 GOP front-runner, faces four federal charges, including conspiracy to defraud the United States, conspiracy to obstruct an official proceeding, obstruction of and attempt to obstruct an official proceeding, and conspiracy against rights.

The former president is expected to travel from Bedminster, New Jersey, to Washington, D.C., on Thursday. He was ordered to appear in federal court for a 4 p.m. arraignment.

This is the second federal indictment the former president faces out of Smith’s investigation. Trump, who leads the 2024 GOP presidential primary field, has already pleaded not guilty to 37 counts related to his alleged improper retention of classified records from his presidency.

Those charges include willful retention of national defense information, conspiracy to obstruct justice and false statements. Trump was charged with an additional three counts as part of a superseding indictment out of that probe last week.

Trump is the first former president in U.S. history to face federal criminal charges. 

Fox News' Brooke Singman contributed to this report. 

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