if you allow the president to preemptively pardon crime then you are not pardoning, you are immunizing. biden can say that fauci will be pardoned for all crimes in the criminal code going forward, then fauci can go and rape a bitch and he can't be tried because that crime has been pardoned.  trump could pardon himself for any crime after the fact, which would give him total immunity, he could stage a coup and could not be convicted, plus he can give that immunity to everyone.
Spain