David Berkowitz terrorized New York City by killing six people and wounding seven others in seemingly random shootings from July 1976 to July 1977. In his first major TV interview in a decade and his only interview about the 40th anniversary of his arrest, Berkowitz -- who is serving six consecutive life sentences -- speaks out to CBS News correspondent Maurice DuBois about what led him to kill, his life before he turned into a murderer, and what his life is like in prison today.