VANCOUVER (Reuters) - Canada's highest court refused on Friday to grant a new trial for serial killer Robert "Willie" Pickton, who was convicted of killing drug addicts and prostitutes and butchering their remains at his pig farm.
The Supreme Court rejected Pickton's claim that his rights were violated during a lengthy trial that resulted in him being convicted in 2007 of the murders of six women whose partial remains were found on his ramshackle property near Vancouver.
"Certainly this was a long and difficult trial, but it was also a fair one," Supreme Court Justice Louis Lebel wrote.
The ruling means Pickton, 60, will not face trial for an additional 20 murders he is charged with. Prosecutors say the second trial is unneeded because he is already sentenced to life in prison. Canada does not have a death penalty.
The victims were among more than 60 women who disappeared from Vancouver's poor, drug-infested Downtown Eastside neighborhood over more than a decade until Pickton's arrest in early 2002.
His trial heard gruesome testimony of how Pickton brought prostitutes to his property in Port Coquitlam, British Columbia, then killed them and cut up their bodies in the farm's slaughterhouse.
Pickton never testified, but there was evidence that he admitted to killing 49 women. DNA or remains of 33 women were found on the farm, but prosecutors brought charges in only 27 cases, with one case later dismissed by the trial court.
Pickton was the only person charged with the murders, but his lawyers argued other people could have been responsible for the deaths. The appeal argued the judge erred in saying Pickton could be convicted even if others were involved.
The victims' families have demanded an investigation into whether police ignored early warnings that a serial killer was stalking the Downtown Eastside because the women who disappeared were poor drug addicts.
"There needs to be some light cast into the dark corners of the early stages of this investigation," Ernie Crey told CKNW Radio. DNA of Crey's sister, Dawn, was found at Pickton's farm.
Police said they would welcome a public inquiry.
"I would say to the families how sorry we all are for your losses and because we did not catch this monster sooner," Vancouver Deputy Chief Doug LePard told a news conference.
Police said their investigation into Vancouver's missing women continues, including cases that are not linked to Pickton. The police investigation has already cost nearly C$123 million ($119.5 million).
Reporting Allan Dowd, Editing by Peter Galloway