(MIAMI) — Former President Donald Trump is expected to conduct his first known review of classified evidence shared by special counsel Jack Smith as part of his case against Trump for allegedly mishandling the nation’s secrets and obstructing the government’s efforts to retrieve them, sources familiar with the matter tell ABC News.

Trump is scheduled to join his attorneys Tuesday in Miami for a visit to a Sensitive Compartmented Information Facility — or SCIF — in order to view the highly classified materials gathered by Smith’s team over the course of their investigation, including those seized by the FBI during their search of Trump’s Mar-a-Lago estate in August 2022, the sources said.

Trump’s visit comes as the judge overseeing the probe, U.S. District Judge Aileen Cannon, is set to hold a hearing Wednesday in Fort Pierce, Florida, on Trump’s request to extend the deadlines in the case. Cannon has paused any litigation involving the classified materials in question as she considers the request.

Last month, Cannon issued a protective order over the classified information central to the case, clearing the way for the special counsel to begin providing classified discovery materials to Trump and his lawyers to review in the SCIF.

According to public court filings, the material in the classified discovery includes “classified documents that had been stored at Mar-a-Lago as well as other classified material generated or obtained in the Government’s investigation, including documents related to witness interviews such as reports and transcripts.”

It’s standard procedure for defendants charged with illegal retention of national defense information to be able to review the classified evidence gathered against them, while adhering to a strict set of standards and rules barring them from disclosing that information.

Trump pleaded not guilty in June to 37 criminal counts related to his handling of classified materials, after prosecutors said he repeatedly refused to return hundreds of documents containing classified information ranging from U.S. nuclear secrets to the nation’s defense capabilities, and took steps to thwart the government’s efforts to get the documents back. His longtime aide, Walt Nauta, also pleaded not guilty to related charges.

Trump’s lawyers have said they have yet to gain access to a handful of the documents charged in Smith’s indictment against the former president.

The special counsel has said that some documents are so sensitive that even the SCIF isn’t sufficiently secure to store them, requiring alternate arrangements be made for viewing.

“Although the defense SCIF is now approved for the review and discussion of all classified discovery, it is not yet approved for the storage of certain extremely sensitive materials, which the Government has referred to as ‘special measures documents,"” the special counsel wrote in a recent court filing, noting that there are about 127 total pages designated as such.

The special counsel says they have produced about 5,431 pages of classified discovery to Trump and his defense counsel, which includes “four discs of photographs, audio recordings, and material extracted from electronic devices.”

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