Gerald R. Ford: The American Presidents Series: The 38th President, 1974-1977 by Douglas Brinkley:
As it turned out, Nixon already knew what Becker had come to tell him, just as he already knew what Ford was thinking at every step. Al Haig had been keeping his old boss informed of everything that was said in the supposedly confidential Oval Office discussions about a pardon for Nixon. Ford should have known better than to trust his predecessor’s take-charge chief of staff, but he couldn’t grasp the level of deviousness Nixon had provoked in his staff. Gerald Ford’s mistake lay in believing that his White House could operate according to his pledge of “candor and openness” when it remained packed with Nixon holdovers—a number of whom had at least as much reason to want Nixon pardoned immediately as the former president himself did.
For high-level Nixon associates such as Al Haig, Donald Rumsfeld, and Pat Buchanan—not to mention Henry Kissinger—a full-scale trial of the former chief executive posed many potential dangers. At best, such a proceeding would only further cement their ties to the nation’s most scandal-mired administration; worse, a trial might open up new avenues of investigation these aides preferred to remain unexplored.