OTTAWA - The B.C. Crown says it will stay the remaining 20 charges against serial killer Robert Pickton after the Supreme Court of Canada rejected his request for a new trial.

Pickton was convicted in December 2007 for the murders of six Vancouver women.

He appealed his conviction all the way to the high court but today the court rejected his request.

Crown spokesman Neil MacKenzie said Pickton is serving a life sentence with no possibility of parole for 25 years -- the maximum allowed under the law.

The Crown expects to take steps in the "near future" to formally discontinue the remaining prosecutions, he said.

"We recognize that while the family and friends of some of Mr. Pickton's victims understand and accept this position, others have difficulty accepting it," MacKenzie told reporters in Vancouver shortly at the high court announced its decision.

"In reaching this position the branch has taken into account the fact that any additional convictions could not result in any increase to the sentence that Mr. Pickton has already received."

The former pig farmer was charged with 26 counts of first-degree murder, but the trial judge split the charges into two groups and a trial on the remaining 20 charges was put on hold pending the top court's decision.

MacKenzie said the burden of another trial on families, police and the justice system was also a factor in the decision.

Both the Crown and police expressed concern and gratitude to the dozens of families whose loved ones' remains were unearthed on Pickton's farm.

"We hope that this outcome provides them with some degree of comfort and some degree of closure. It has been a long process to reach this stage in the proceedings and we realize it has been difficult and it has required a great deal of patience on the part of family members," MacKenzie said.

The Supreme Court of Canada was unanimous in ruling that Pickton's right to a fair trial was not affected by the trial judge's final instructions to the jury, although they split 6-3 on the reasons.

The appeal centred on a question the jury asked the trial judge on their sixth day of deliberations: jurors wanted to know whether they could find Pickton guilty if they inferred he acted indirectly.

In his answer, the trial judge said if they found Pickton "was otherwise an active participant" in the killings, they could find him guilty.

Pickton's defence had argued that the judge's answer gave the jury an avenue to convict their client without giving them a chance to defend him properly, as the Crown's case rested on Pickton being the only one responsible for the crimes.

In writing for the majority, Justice Louise Charron said that didn't happen:

"Realistically, this case was never about whether Mr. Pickton had a minor role in the murder of the victims. It was about whether or not he had actually killed them."

The court said the evidence that Pickton participated in the murders was "overwhelming."

Pickton was convicted of second-degree murder for the deaths of Mona Wilson, Sereena Abotsway, Brenda Wolfe, Marnie Frey, Andrea Joesbury and Georgina Papin.

Papin's sister, Cynthia Cardinal, said she had mixed feelings about the decision because of the outstanding charges for the other 20 victims and their families.

"I know they deserve to know what happened to their loved ones, too," Cardinal said in an interview from her home in Edmonton. "Although I am very happy that he will never get out and he's convicted for my sister."

Pickton's lawyer was not immediately available for comment.

Pickton's trial followed one of the most massive police investigations in Canadian history, involving thousands of pieces of evidence.

The severed heads, hands and feet of three of the women were found in buckets on his Port Coquitlam, B.C. pig farm, while the bones and DNA of the others were scattered across the property.

The jury heard from Pickton's associates that he bragged about picking up prostitutes and luring them back to his farm to kill them and also heard from Pickton himself, in the form of a lengthy interview with police and with an undercover officer in his jail cell.

In the conversations, he appeared to brag about being the head honcho, and also that he had killed 49 women and wanted to make it one more for an even 50. He also said he had gotten sloppy towards the end.

- With files from Stephanie Levitz in Ottawa