For more than a decade, Janice Knowlton believed she knew the answer to a question that has long intrigued crime buffs: Who killed the Black Dahlia?
Knowlton was 10 years old and living in Westminster when the nude body of Hollywood hopeful Elizabeth Short -- bisected at the waist and drained of blood -- was found Jan. 15, 1947, in a vacant lot in the Leimert Park district of southwest Los Angeles.
More than 40 years later, Knowlton inserted herself into one of the city's most sensational and gruesome unsolved murder mysteries. She said horrifying, long-repressed memories had convinced her that George Knowlton -- her long-dead father -- had murdered Short.
A onetime professional singer and public relations firm owner who lived in Anaheim Hills, Knowlton said she witnessed her rage-filled father beat Short to death with a claw hammer in the detached garage of the family home in Westminster.
Knowlton said that her father had been having an affair with Short and that Short was staying in a makeshift bedroom in their garage, where she suffered a miscarriage. Knowlton said she was later forced to accompany her father when he disposed of the body.
In 1991, she persuaded skeptical Westminster police detectives to search for evidence of the Black Dahlia murder -- and that of another murder she believed her father committed -- by excavating a vacant lot, the site of her former home. Nothing to warrant a criminal investigation was found.
But appearances on "Larry King Live," "Sally Jessy Raphael" and other TV shows followed, as did the 1995 book "Daddy Was the Black Dahlia Killer," which Knowlton wrote with Michael Newton and which chronicles her lurid tale of incest, rape and multiple murders.
Though she later slipped from the limelight, Knowlton remained obsessed with the Black Dahlia and over the years continued offering her input into the bizarre mystery.
"Any time we ran anything about the Black Dahlia case, she'd leave long, rambling voice messages on my answering machine at The Times," said Larry Harnisch, a Times copy editor who wrote about the Black Dahlia for the paper in 1997 and is writing a book on the case.
But he did not hear from Knowlton after the 2003 publication of "Black Dahlia Avenger: A Genius for Murder," a book by retired LAPD Det. Steve Hodel that became a national bestseller. In it he makes a compelling but controversial case that it was his own father, the late physician George Hodel, who murdered Short.
Recently, Harnisch's curiosity was piqued by Knowlton's silence after a Nov. 21 Los Angeles Times Magazine article on Hodel. Harnisch began investigating and discovered that Knowlton, 67, had died March 5 at her home. The Orange County coroner's office classified the death, which escaped public notice, as a suicide from the combined effect of five drugs.
Jolane Emerson, Knowlton's stepsister, told The Times last week she didn't believe that Knowlton, who took various prescribed medications, had meant to kill herself.
"I think what happened is she just overdosed accidentally," Emerson said.
She acknowledged that her stepsister's alleged memories, which included Knowlton's assertion that her father molested her when she was a child and that he sadistically killed others besides Short, strained family relationships.
"Her book was trash, and it wasn't even true," Emerson said. "She believed it, but it wasn't reality. I know, because I lived with her father for 16 years."
Emerson said her stepfather, a foundry worker who died in a 1962 car crash with his young son Kevin, "could be meaner and ornerier than heck, but he wasn't a killer."
Police in Los Angeles and Westminster placed little credence in Knowlton's Black Dahlia story when it surfaced.
"The things that she is saying are not consistent with the facts of the case," John P. St. John, an LAPD homicide detective, told The Times in 1991.
Psychiatrists and experts on post-traumatic stress disorder who appeared with Knowlton during her talk-show appearances, however, found her story plausible.
The Boston-born Knowlton, who moved from Lynn, Mass., to Westminster in 1945, said she had been suffering from depression, anxiety and panic attacks for a number of years when she underwent a hysterectomy in 1985.
After a massive injection of estrogen, according to her book, her health deteriorated rapidly. At the same time, she experienced intensified feelings of terror and had persistent thoughts of suicide, she said.
Jim Frey, Knowlton's therapist and a specialist in adults who were abused as children, spoke to The Times for a 1993 story on Knowlton. He said studies of post-traumatic stress disorder had found that replicating the adrenaline-charged state a person was in when first traumatized could trigger emotional responses or memories of the event.