A chief investigator said Tuesday he purposely misled an accused serial killer about what his friends and brother had told police.

Robert Pickton is accused of killing 26 women but is on trial for the first six counts. If found guilty of 14 of the murders, he would become the worst convicted killer in Canada.

Investigators say he threw drunken raves at his pig farm with prostitutes and drugs. After his arrest in 2002, health officials issued a tainted meat advisory to neighbors who may have bought pork from his farm, concerned that it may have contained human remains.

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Royal Canadian Mounted Police Inspector Don Adam admitted to misleading Pickton when he said Pickton's friend was cooperating in the investigation in an effort to get him to confess to the crimes.

"My understanding at that time is that her parents wanted her to cooperate with the investigation," Adam said. "But I'm being misleading with him when I'm indicating that things are quite rosy and that she's going to get on board. She never got on board at all."

"It's called a lie," Pickton's attorney, Peter Ritchie, countered.

Adam also said he thought he told Pickton that Pickton's brother Dave was going to testify against him.

Ritchie pointed that three Pickton acquaintances had also been arrested on suspicion of murder, though none but Pickton was ever charged.

Adam also told Pickton that his brother told investigators that Pickton's friend, Dinah Taylor, was killing the women and Pickton was only getting rid of the bodies.

Last week, the court watched a videotaped interrogation in which Pickton appeared to acknowledge some of the murders, then said he had nothing to do with them.