When a Supreme Court judge swears him in he is the LEGAL PRESIDENT.
Wrong
10 Interesting Things You Should Know About Inauguration Day
http://history1900s.about.com/od/fadsfashion/a/inauguration.htm
Although it is not stipulated in the Constitution, it has become a tradition to have the Chief Justice of the Supreme Court be the oath giver to the President on inauguration day. This, surprisingly, is one of the few traditions of inauguration day not begun by George Washington, who had the Chancellor of New York Robert Livingston give him his oath (Washington was sworn in at Federal Hall in New York). John Adams was the first President to have a Chief Justice of the Supreme Court swear him in.
Quit trying to evade your Grade School assertion.
It makes no difference if the SCOTUS or his Aunt Sally gives the President the Oath of Office the effect is the same, the person giving the oath is the legal President. Anything preventative must be done prior to that oath.
Don’t misunderstand, I wish there was some magic wane we could wave and this asshole would disappear, but there isn’t any and we, as America loving patriots are obligated to operate in Realville.