Under our constitutional structure of separated powers, the nature of Presidential power entitles a former President to absolute immunity
from criminal prosecution for actions within his conclusive and preclusive constitutional authority. And he is entitled to at least presumptive immunity from prosecution for all his official acts
In dividing official from unofficial conduct, courts may not inquire
into the President’s motives. Such a “highly intrusive” inquiry would
risk exposing even the most obvious instances of official conduct to judicial examination on the mere allegation of improper purpose. Fitzgerald, 457 U. S., at 756. Nor may courts deem an action unofficial
merely because it allegedly violates a generally applicable law.
This case poses a question of lasting significance: When may a
former President be prosecuted for official acts taken during his Presidency? In answering that question, unlike the political branches and
the public at large, the Court cannot afford to fixate exclusively, or
even primarily, on present exigencies. Enduring separation of powers
principles guide our decision in this case. The President enjoys no immunity for his unofficial acts, and not everything the President does is
official. The President is not above the law. But under our system of
separated powers, the President may not be prosecuted for exercising
his core constitutional powers, and he is entitled to at least presumptive immunity from prosecution for his official acts. That immunity
applies equally to all occupants of the Oval Office.
Just to add some more fun quotes: