These Docs predate Biden as POTUS.
Meaning he stole them from a SCIF.
How does he know what was in those boxes in the bathroom. Trump had to have hundreds of boxes with personnel papers after four years.
It doesn’t make any difference. Trump makes the sole determination. There is no higher authority in the Executive branch than President. Trump does not need permission or process to possess any document. Congress does not have the power to do anything either. The appropriate thing for Trump to say is that everything is personal.
A key to reading any statute or Executive Order on the subject is to understand that they are written for everyone other than the President. The President doesn’t write EO’s to order himself. Congress cannot change fundamental powers in the Constitution. Their check and balance is the power of oversight and the power of the purse. Congress can’t tell the President to do a damn thing.