While Kennedy deserves no respect for his actions at Chappaquidick, the writer of this book isn't exactly the epitome of intellectual rigor.
"Klein's books have been dismissed by academics and journalists as "not only psychobabble," but "psychoblarney." An example of the criticism:
The Boston Herald has quoted him calling the late Carolyn Bessette Kennedy "a disturbed, neurotic, unstable young woman"; according to the Buffalo News, Klein's book The Kennedy Curse described Bessette Kennedy "sprawled on the floor in front of a sofa, disheveled and hollow-eyed, snorting cocaine with a gaggle of gay fashionistas." The News book review called The Kennedy Curse "a contrived and stretched effort that seeks legitimacy by surrounding a few interesting scoops with historical and psychological analysis," adding of one Klein passage: "He takes a long and involved analysis of Ireland's Great Famine of the 1840s, links it to the emigration of JFK's great-grandfather to Boston, and applies enough psychobabble to explain everything from President Kennedy's womanizing to William Kennedy Smith's celebrated rape trial in 1991."
He came under fire for his biography of Hillary Clinton entitled, The Truth about Hillary: What She Knew, When She Knew It, and How Far She'll Go to Become President which was released on June 21, 2005. On the day of its release Sean Hannity interviewed him on the radio. Radio host Al Franken, along with Joe Conason interviewed him on Air America that month as well. During the interview, Franken and Conason exposed inaccuracies in Klein's book, including incorrect names and deliberate omissions from quotes with the intention to deceive the reader. Klein claimed that he was not told that Conason, who had authored The Hunting of the President in defense of the Clintons, would join the interview, but Franken asserted that Klein's publicist was informed that Conason would help conduct the interview."