Mass murder on Long Island: the crime and prosecution of 23-year-old Ronald ""Butch"" DeFeo--who awoke early one morning in November, 1974, shot all six other members of his family in their beds, then showered and went to work. Later that day he ""found"" the bodies and basked briefly in police pity as the sole survivor of the tragedy; but his wild tale of a Mafia contract hit didn't ring true. Pressed, he confessed. Aronson and Sullivan--the ambitious, arrogant (""lack of confidence is not one of my problems"") young prosecutor who pushed himself into the case--try hard to build the story of a young thug run amok into a symbolic suburban tragedy (""Ocean Avenue was a street of American dreams""). But the result is little more than a flat police procedural, capped by an overlong, blow-by-blow account of the trial. Despite references to ""a subculture. . . stripped bare,"" the authors fail to explain what drove DeFeo, ""a high school dropout, inept at all sports, unskilled,"" to cross the line from violence-prone carousing at South Shore ginmills to the senseless killing of his family. ""Once I started,"" said Butch, ""I just couldn't stop."" Was he insane? Psychiatrists' testimony (well-covered here) was conflicting, but Sullivan's adroit baiting of DeFeo on the witness stand brought out the ""antisocial personality"" of the killer (""I couldn't care less what happens in this courtroom""), and the jury rejected the insanity defense. The bottom line: Sullivan (like him or not) got the victory he deserved, DeFeo got 25 to life, and the house where it all happened became very famous under new ownership. But creepy, unanswered questions remain: Why didn't any of the victims resist? Why didn't they hear the shots? Why were they all found face down in bed? Unsatisfying--but don't underestimate the Amityville hook.