(NewsNation) — The so-called hush money case against former President Donald Trump involving porn star Stormy Daniels has garnered widespread attention from the press as Trump is set to be arraigned Tuesday.

The historic indictment raises many questions about what legal procedures will be followed. One attorney representing Trump told CNN these are uncharted waters.

“Obviously this is different. Never had secret service involved in an arraignment at 100 Centre St. So the answer is I honestly don’t know how this is gonna go,” said Joe Tacopina, one of the lawyers representing Trump, on CNN’s State of the Union.

It’s expected the former president will have his mug shot and fingerprints taken Tuesday, but Reuters reports handcuffing him is off the table. Following that, the indictment will be unsealed and Trump will enter a plea.

“We will very loudly and proudly say not guilty,” Tacopina told CNN.

The key witness for the prosecution in this case is Trump’s former fixer, Michael Cohen, who allegedly made the $130,000 hush money payment to Stormy Daniels. But some question Cohen’s credibility since he is a convicted perjurer, but he insists his testimony is reliable.

“Yes, I lied to congress. At the direction of and in coordination and benefit of Donald J. Trump. And if there’s anyone out there that thinks that lie will prevent me from being credible witness based on docs, recording, testimony, emails, reporting, it’s not gonna happen,” Cohen said on CBS’s Face the Nation.

The Associated Press reported Trump is expected to face at least one felony charge, citing an unnamed source.

The full list of Trump’s exact charges will remain unclear until the indictment is unsealed Tuesday.

Once the arraignment is over, a lengthy legal process is likely to follow. It could take as long as a year before a trial happens, if ever, according to James Sample, professor of constitutional law at Hofstra University.

If it does go to trial, former attorney general William Barr does not believe Trump should testify.

Barr, who served under Trump, told Fox News Sunday, “It’s particularly a bad idea for trump because he lacks all self control, and it would be very difficult to prepare him and keep him testifying in a prudent fashion.”