SMITH'S FAMILY WAS DEEPLY TROUBLED

AsSusan Smith's attorney neared the end of her defense, a psychiatrist today pressed the notion that she -- like her abusive father, Harry Vaughn -- maskedserious mental illnesswith a pleasant demeanor. The psychiatrist described how Vaughn, who shot himself to death 17 years ago, once held her mother at gunpoint with their young daughter present. By 1994, when Smith's then-husband, David Smith, left their home for good, he said, she fell into "a desperate searching to deal with the loneliness" -- with heavy drinking, thoughts of suicide and simultaneous sexual relationships with at least three men, including her stepfather, Beverly Russell, a local GOP official and Christian Coalition leader. Defense lawyer David Bruck, who has not said whether he will put Smith on the stand, plans to wrap up his case late today or Saturday.