Complex sentence: As White House Counsel, he became deeply involved in events leading up to the Watergate burglaries and the subsequent Watergate scandal cover up, even referred to as "master manipulator of the cover up" by the Federal Bureau of Investigation (FBI).
Split into simpler sentences: As White House Counsel, he became deeply involved in events leading up to the Watergate burglaries and the subsequent Watergate scandal cover up. He was referred to as "master manipulator of the cover up" by the Federal Bureau of Investigation (FBI).