Here's a possible answer. It might be a timing issue.
>>>Ciara Torres-Spelliscy, a professor at Stetson University College of Law in Florida, said the risk of paying defense attorneys with contributions is that the FEC or the Justice Department
may later decide that it was an illegal personal use of campaign funds. She doubted such a case would be brought against Trump now because doing so might slow the ongoing federal prosecutions overseen by Justice Department Special Counsel Jack Smith.
“But after the Mar-a-Lago and January 6th cases are done,
I would not be surprised to see a personal use case against Trump for using these millions in donations that are meant to go to his political campaign going instead for the personal use of keeping him out of prison,” Torres-Spelliscy said.<<<
Trump’s Save America political action committee has paid nearly $37 million to more than 60 law firms and individual attorneys since January 2022, records show.
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I've also heard unconfirmed reports that Trump's PAC includes a statement to the effect that the donor agrees that the money can be used for personal expenses. I have not gone to his PAC website to make a donation so I'm not sure if this is correct. Also, even if there is such a disclaimer, I'm not sure that this would shield him from a charge that he illegally used campaign funds for personal use. Off hand, it seems contradictory to say that he can treat the same money as both a campaign contribution and a personal donation.
Trump's legal problems might get significantly worse before too long.