A former sex worker who survived an attack on serial killer Robert Pickton's farm five years before his arrest, only to see charges against him dropped, has decided against testifying at the public inquiry into the case.

The woman, who is being referred to by the pseudonym Ms. Anderson, was scheduled to testify this week, but commission lawyer Art Vertlieb told the hearings Tuesday that the woman no longer wants to appear.

"Ms. Anderson has for many, many months consistently been concerned about her privacy, the privacy of her husband, the privacy of her three children, her parents and her family," Vertlieb told the inquiry.

"We have interviewed Ms. Anderson more than once, and it's clear that she's turned her life around admirably. ... She very much wants to keep it that way. She has suffered a horrific event and I would suggest that no one in this courtroom would truly imagine or understand the enormity or the gravity of the event that she went through."

Vertlieb said he respected the woman's decision and didn't plan on compelling her to appear. He said he believed the inquiry can conduct its work without her testimony.

"Should Ms. Anderson change her mind, we would welcome her coming here," Vertlieb said.

Anderson was attacked in March 1997 after going with Pickton to his farm in Port Coquitlam. She was sent to hospital with life-threatening injuries, and Pickton was later charged with charges that included attempted murder.

In January 1998, prosecutors stayed the charges, citing concerns about Anderson's reliability.

That decision is under scrutiny at the public inquiry, and the Crown counsel who entered the stay of proceedings, Randi Connor, was scheduled to testify Tuesday afternoon.

Two dozen women later connected to Pickton's farm disappeared between March 1997 and Pickton's arrest in February 2002, including 19 women who vanished after the Crown's decision to stay the charges in January 1998.

After Pickton's arrest in 2002, forensic investigators found the DNA of three missing women on evidence seized after the 1997 attack, including clothing and a condom package.

Anderson testified at the preliminary hearing before Pickton's trial, but she never told her story to the jury. The details were under a publication ban until August 2010, when the Supreme Court of Canada rejected Pickton's final appeal of his six second-degree murder convictions.

She told the preliminary hearing that Pickton picked her up in Vancouver and drove her to his farm in Port Coquitlam.

After they had sex, Pickton slipped a handcuff onto one of her wrists, she testified. She grabbed a knife and slashed him across the neck and arm. Pickton managed to stab her before she ran outside and down the road.

A couple driving past noticed Anderson, picked her up and brought her to hospital, where she was treated for injuries so severe that her heart stopped twice on the operating table. She was still holding the knife when she was picked up, and the handcuff was still on her wrist.

Pickton arrived later at the same hospital and a key was found in his clothes. It matched the woman's handcuff.

Pickton was charged with several charges including attempted murder and forcible confinement.

But in January of the following year, Crown counsel stayed the charges over concerns that Anderson, who was addicted to drugs and had missed several meetings with prosecutors, would be an unreliable witness.

The inquiry has already heard that evidence seized from Pickton after the 1997 attack sat for years in an evidence locker without being examined for DNA.

When it was finally tested after Pickton's arrest in 2002, investigators found the DNA of three missing women.

Jacqueline Murdock's DNA was found on the outside of condom packages, Andrea Borhaven's DNA was found on Pickton's boots and Cara Ellis's DNA was found in his jacket.

The inquiry heard from the civilian RCMP lab worker who testified that even if the evidence was tested sooner, investigators wouldn't have known who the DNA belonged to because they didn't have profiles of the missing women.

Pickton's arrest in 2002 set off a massive search of his farm in Port Coquitlam, where the remains or DNA of 33 women were found.

He was convicted of six counts of second-degree murder, though he once told an undercover police officer that he killed 49 women.