According to the news sources , Yahoo, Bush authorized Libby to leak secret information and Chaney is probably involved. Sounds like federal offensed to me. If they both are removed here, from the Cornell Law School US Code collection, is the "Law of Presidential Succession":


TITLE 3 > CHAPTER 1 > § 19 Prev | Next

§ 19. Vacancy in offices of both President and Vice President; officers eligible to act
Release date: 2006-03-20

(a)
(1) If, by reason of death, resignation, removal from office, inability, or failure to qualify, there is neither a President nor Vice President to discharge the powers and duties of the office of President, then the Speaker of the House of Representatives shall, upon his resignation as Speaker and as Representative in Congress, act as President.
(2) The same rule shall apply in the case of the death, resignation, removal from office, or inability of an individual acting as President under this subsection.
(b) If, at the time when under subsection (a) of this section a Speaker is to begin the discharge of the powers and duties of the office of President, there is no Speaker, or the Speaker fails to qualify as Acting President, then the President pro tempore of the Senate shall, upon his resignation as President pro tempore and as Senator, act as President.