The author who helped Trump write some of his books has a theory about why the former president might have taken some documents.

The author of "Surviving at the Top" worked with the former president in the 90s and commented on the FBI's search of Mar-a-Lago.

After leaving the White House, Trump may have brought some material to his home in Florida. The National Archives asked the DOJ to investigate whether or not Trump broke the law when he took government records from the White House to his private club.

His theory was that Trump could have taken documents.

Leerhsen said that he felt obligated to point out that Trump may have taken documents that he intended to sell.

Leerhsen told Newsweek that he had seen how Trump earned his money before he went into politics. According to Newsweek's report, Leerhsen acknowledged that he did not know what Trump might have taken, but speculated that pieces of paper he signed or collectible items could be what the former president wanted to keep.

He's going to grift it if there's a grift to it. He has a sense that he can pawn it off.

He said he used to have a "firsthand sense" of Trump's personality.

Leerhsen told Newsweek that he watched things spiral out of control.

Representatives for Trump did not reply to a request from Insider.