Michele Pineault said an official with the B.C. Corners Service met with her last September and gave her fragments from two vertebrae belonging to her daughter, Stephanie Lane, who was 20 when she vanished in January 1997.
Lane is among six women whose DNA was found on Pickton's farm but whose cases did not result in any charges.
Pineault said prosecutors told her at the time that Lane's DNA was found in a freezer, which wasn't enough to proceed with charges. She said she was never told about the bone fragments' existence.
"I was told that .. if there had been more (than DNA), it would have been enough to charge him," Pineault hold a news conference in Vancouver, holding a pair of small plastic bags containing her daughter's remains.
"I want Robert Pickton charged with my daughter's murder."
However, it quickly became apparent that no new charges will be laid.
The B.C. Corners Service said in a statement that the remains were known to police during the original investigation and "do not represent new evidence."
Crown spokesman Neil MacKenzie said prosecutors also knew about Lane's remains when they made their decisions about charges. He repeated the criminal justice branch's long-standing position that Pickton will not be prosecuted for additional murder charges.
Pickton was arrested in 2002, setting off an exhaustive search for human remains on his farm in Port Coquitlam, east of Vancouver.
Investigators found the remains or DNA of 33 women.
Pickton was eventually convicted of six counts of second-degree murder, and prosecutors then stayed another 20 murder charges because the serial killer had already received the maximum sentence under the law. A 27th murder charge involving a woman referred to only as Jane Doe, whose remains were found on the property, was dropped.
No charges were ever laid in the deaths of six other women, including Lane, whose remains or DNA were found on the farm.
Pineault said getting her daughter's remains opened up painful wounds.
"I have no words," said Pineault, who was wearing a shirt emblazoned with a photo of Lane.
"They told me that she was very safe in a storage locker. She should have been at home years and years and years ago."
RCMP said in a statement that the force turned over the victims' remains following the Supreme Court of Canada decision in 2010 upholding Pickton's conviction.
The coroners service said it could not explain why Lane's remains were not returned as soon as the agency received them from the RCMP.
"The B.C. Coroners Service has apologized to the family of Ms. Lane, and does continue to extend its sincere apologies for any further stress caused them by the delay," the statement said.
The province's attorney general, Suzanne Anton, said in a written statement that the current chief coroner has implemented "safeguards to prevent similar instances."
Pineault said Lane had a son, who was just eight months old when his mother vanished.
"She was very exuberant, happy," Pineault said.
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