Trump doubles down on 'total immunity' claims, Haley pushes back

Donald Trump is doubling down on his claims of "complete and total" presidential immunity as he awaits a decision from an appeals court on his effort to have his federal election interference case dismissed.

Trump, appearing to go further than before, wrote on his social media platform on Thursday, in all caps, that even “events that ‘cross the line’ must fall under total immunity” or else there would be “years of trauma trying to determine good from bad.”

Later that day, during an interview with Fox News host Sean Hannity, Trump continued to make his case -- unprompted.

Hannity asked Trump to deliver a closing message to New Hampshire voters, who will cast their ballots in the GOP primary on Tuesday.

The former president briefly responded that his message is "Make America Great Again" and then launched into remarks on his legal troubles.

"If a president is afraid to act because they're worried about being indicted when they leave office -- a president of the United States has to have immunity. And the Supreme Court's going to be ruling on that," he said. "If they don't have immunity, no president is going to act. You're gonna have guys that just sit in office and are afraid to do anything.”

Constitutional scholar Michael Gerhardt, a law professor at University of Chapel Hill, expressed deep skepticism about Trump's claim that he is entitled to total immunity from criminal prosecution.

"I would describe it as a dangerously bad argument," Gerhardt told ABC News. "It contradicts nearly everything we know about the Constitution and the intent of the framers."

Gerhardt continued, "It would be an argument that might make sense if the president were king, but he's not king."

Trump's latest comments also received pushback from one of his Republican rivals.

Nikki Haley, who is looking to beat Trump in New Hampshire's open primary, was asked to respond to Trump's social media post on immunity during a CNN town hall on Thursday night.

Haley said it should be "common sense" that presidents can't do whatever they want with no repercussions.

“It should be common sense, right? Common sense," she said. "Obviously, if a president is doing something and it's related to, you know, whether it's terrorist threats or something like that and people die, that's one thing."

"But do you get just total freedom to do whatever you want? No, that's never the way it was intended to be," she continued. "There needs to be accountability. No one is above the law."

Still, Haley said if president she would pardon Trump if he is convicted because him going to jail would only "further divide our country."

The three-judge panel from the U.S. Court of Appeals also seemed extremely wary of Trump's case when they heard arguments earlier this month.

One judge called Trump's arguments "paradoxical" and another asked if his team was saying a president could sell pardons or order the military to assassinate a rival with no consequences.

Trump's attorney argued that any criminal prosecution of a president for action taken while in office is only possible if they are both impeached and convicted first.

The appeals court has not indicated when a decision will be made. But the case could well wind up before the U.S. Supreme Court depending on how the process plays out.

The Supreme Court previously ruled, in a case involving former President Richard Nixon, that presidents can't be held liable in civil cases for actions they undertook as part of their official duties.

There are no Supreme Court rulings, however, on whether sitting or former presidents are immune from criminal charges related to their actions while in office. That's because Trump is the first current or former president to ever be criminally indicted.

-ABC News' Abby Cruz, Lalee Ibssa and Soorin Kim contributed to this report.