VANCOUVER - Convicted serial killer Robert Pickton has lost an attempt to overturn his second-degree murder convictions and land a new trial in the deaths of women from Vancouver's Downtown Eastside.

In a split decision released Thursday, B.C.'s top court rejected Pickton's arguments that his 2007 trial "went off the rails" in the middle of jury deliberations because of alleged errors made by the trial judge.

But the decision doesn't resolve the complex legal process that has wound its way through B.C. courts for the better part of the decade.

The defence could still try and take its case to the Supreme Court of Canada.

One of Pickton's lawyers didn't offer any clues immediately after the decision was released.

"It's going to take some time for us to review and analyse these materials," lawyer Patrick McGowan said. "We'll consider our options."

Pickton's appeal centred on the original trial judge's response to a question posed by the jury in the middle of deliberations.

Pickton's defence argued the trial judge didn't fully understand the question posed by the jury during deliberations, erred in his response to the question, then changed his original instructions to the jury, essentially expanding the circumstances under which Pickton could have been convicted.

But the B.C. Court of Appeal disagreed in its split decision.

"In my opinion, the trial judge ultimately answered the jury question in a correct and sufficiently comprehensive manner, "wrote Justice Richard Low in his decision, which was supported by Chief Justice Lance Finch.

Justice Ian Donald dissented.

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

In a complex, multilayered decision, the B.C. Court of Appeal also armed the Crown with the tools to retry Pickton on all 26 counts of first degree murder the Port Coquitlam pig farmer originally faced, should a new trial ever be ordered.

Crown has said it won't pursue a new trial if the courts uphold Pickton's convictions.

Irwin Loy reports for Vancouver 24 hours.