NYT on Nixon Watergate tapes; Judge Lamberth

Notice the following sentence structure in a New York Times story about the Nixon Watergate tapes [ Judge Orders Release of Nixon’s Watergate Testimony ]:

With the possible penalty of perjury over his head, Professor Kutler said, “My guess is he told those people the truth.”
Antecedent for "his"?

The judge in the case was Royce C. Lamberth III of the Federal District Court for the District of Columbia. Lamberth was involved in the federal funding for stem cell case, and "the meaning of research."