http://www.history.com/topics/vietnam-war/pentagon-papers

Hi there!
This link above would lead you to the Pentagon Papers vs US case. The book unfortunately does not tell us extra about that case. In a previous chapter we read about the Watergate scandal and Nixon and  story behind it begun from Pentagon Papers or New York Times vs US; This info will make sense, when Nixon will be resigning and the reason why US started investigation on Nixon will reveal all secrecy.