FIRST ON FOX: Legal experts tell Fox News Digital it makes little difference whether former President Trump declassified the documents at the heart of his federal indictment.

Under the Espionage Act, the crime would be improper retention or disclosure of sensitive defense information, not classified documents, according to former Assistant U.S. Attorney Andy McCarthy, who told Fox News Digital that he's "argued for a long time that Trump’s declassification claims are a red herring."

"The Espionage Act crime is willful retention of national defense information, not classified information," McCarthy said. "There is no actual evidence that Trump declassified documents, but even if he did, that would not mean the documents aren’t national defense information."

"Moreover, as for the obstruction charges, the grand jury subpoena required him to surrender all documents physically bearing classification markings; so, again, even if he had declassified them, that would be irrelevant because the subpoena did not hinge on whether the documents were still classified – just whether they were marked classified," he added.

Trump is scheduled for an initial court hearing Tuesday after a federal grand jury indicted him Friday on 37 charges related to his retention of sensitive documents. His indictment has led to calls for Special Counsel Robert Hur to bring similar charges against President Biden.

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Former President Donald Trump

Former President Donald Trump is set to be arraigned Tuesday after he was indicted Friday on 37 charges related to his retention of sensitive documents. (Scott Olson/Getty Images)

Richard Painter, a law professor at the University of Minnesota, told Fox News Digital in a Monday phone interview that documents are either classified or declassified, and that the president, alongside some others, has the authority to declassify documents.

"And so if documents are declassified, then none of the criminal prosecutions that could be based on classification of the documents would survive, only the national defense information, which is a separate category," Painter said.

Though much national defense information is classified, some is unclassified – but would still be covered by the Espionage Act. 

"So I do think it's important, you know, whether documents classified or not, because if there are any declassified, then any and all criminal counts that refer to classified documents would not apply to the documents that were declassified," Painter added.

Painter also pointed out that the boxes of documents that went with Biden after he left the office of the vice president "should have been checked on the way out for classified documents and they should have been checked when they arrived at their destination."

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"You cannot remove originals of any document without violating the Presidential Records Act," Painter said. "And so, particularly when they're in a rush to pack things, every single one of those boxes should have been reviewed again immediately upon arrival at its destination, in addition to a much more careful review on the way out."

"And we need to find out what happened and make absolutely sure that never happens again, as I hope with that Mike Pence documents," Painter continued, noting that the "second issue" is the locations at which Biden’s documents were kept.

"The second issue is that those documents were held in locations where there could have been access to those documents by foreign nationals and others who were not authorized to see them," he warned.

Richard Painter

Richard Painter, a law professor at the University of Minnesota, told Fox News Digital that the president, alongside some others, has the authority to declassify documents. (CQ-Roll Call/Getty Images)

"We need to do the best we can or the investigators do to reconstruct who was in those buildings where the documents were," he added.

The indictment of Trump in Special Counsel Jack Smith's investigation is casting renewed attention onto another, similar probe – Hur's investigation into Biden's handling of classified documents.

Andy McCarthy

Andy McCarthy told Fox News Digital that he’s "argued for a long time that Trump’s declassification claims are a red herring." (Fox News)

Several troves of classified documents, some reportedly dating back to Biden's Senate days, were found in the president's possession within the last year, including documents found at the Penn Biden Center in Washington, D.C., as well as in the garage of his Wilmington, Delaware, home. In January, Attorney General Merrick Garland named Hur as special counsel overseeing the Biden probe.

George Washington University law professor and Fox News contributor Jonathan Turley told Fox News Digital the "question is whether Hur will aggressively pursue the possibility of false statements by President Biden and whether he has requested an interview with the president."

"As I have previously noted, Biden's account of the handling of the documents defies logic," Turley said. "These documents appear to have been moved and repeatedly divided. One reportedly was found in or near his library."

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"The Senate documents had to be removed from the SCIF by then-Sen. Biden. The handling of these documents suggest a purpose and knowledge," Turley continued.

"Hur can insulate President Biden by avoiding a direct interview or statement from him on these facts. It is a crime to lie to federal investigators under 18 U.S.C. 1001. With Trump, the Justice Department was highly aggressive. The public is likely to watch to see if Hur shows the same no-holds-barred attitude of Smith."