In the military, we have the UCMJ that allows us to prosecute those military personnel that issue illegal orders. The President is the Commander-in-Chief, but he is a civilian, so the UCMJ doesn't apply. I always thought he would be charged under criminal law in that case, but it seems that this ruling precludes that.
Page 14 notes that the President's official responsibilities "include, for instance, commanding the Armed Forces of the United States; granting reprieves and pardons for offenses against the United States; and ap- pointing public ministers and consuls, the Justices of this Court, and Officers of the United States."
Page 17 states "We thus conclude that the President is absolutely immune from criminal prosecution for conduct within his exclusive sphere of constitutional authority."
Page 26 states "In dividing official from unofficial conduct, courts may not inquire into the President’s motives."
Right below that it clarifies
> If the President claims authority to act but in fact exercises mere “individual will” and “authority without law,” the courts may say so. Youngstown, 343 U. S., at 655 (Jackson, J., concurring). In Youngstown, for instance, we held that President Truman exceeded his constitutional authority when he seized most of the Nation’s steel mills. See id., at 582–589 (majority opinion). But once it is determined that the President acted within the scope of his exclusive authority, his discretion in exercising such authority cannot be subject to further judicial examination.
Absurd, to the point of being hilarious. Could a president use this (immunity and nukes) to become an absolute ruler?
Edit: a failsafe is there, see sibling comment: https://news.ycombinator.com/item?id=40849357
If the president is able to bring physical power to bear, then it matters little what the law says anyway.
Congress, through impeachment.
