In May, shortly before the raid, an anonymous employee testified that Trump himself ordered him to move boxes of classified documents out Trump's residence.

Played down by the New York Times, his testimony was backed up by video proof of the boxes being moved, plus the employee snapped pictures of the boxes in its new location.

So it's not a case if Trump actively attempted to hide secret documents; it's a case of how much more happened.

New York Times: Justice Dept. Intensifying Efforts to Determine if Trump Hid Documents

Federal prosecutors investigating former President Donald J. Trump’s handling of classified documents have obtained the confidential cooperation of a person who has worked for him at Mar-a-Lago, part of an intensifying effort to determine whether Mr. Trump ordered boxes containing sensitive material moved out of a storage room there as the government sought to recover it last year, multiple people familiar with the inquiry said.

Through a wave of new subpoenas and grand jury testimony, the Justice Department is moving aggressively to develop a fuller picture of how the documents Mr. Trump took with him from the White House were stored, who had access to them, how the security camera system at Mar-a-Lago works and what Mr. Trump told aides and his lawyers about what material he had and where it was, the people said.

At the heart of the inquiry is whether Mr. Trump sought to hide some documents after the Justice Department issued a subpoena last May demanding their return.
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