Sex assault charges have been stayed against a serial violent offender after he had to wait more than six years to go to trial in B.C.

Oliver James Doherty was charged with sexual assault, unlawful confinement and uttering threats for allegedly attacking a woman inside a bus he had been driving in New Westminster on Feb. 7, 2010, according to court documents. A warrant was issued for his arrest in October 2011.

But even though Doherty was already in jail in Alberta, the warrant wasn't executed until four and a half years later, and his trial in this province has yet to take place.

B.C. Supreme Court Justice Michael Tammen described that delay as "clearly unreasonable" and said the fault lay almost entirely with Crown prosecutors.

"The Crown in this case had no solid plan for bringing the matter to trial in a reasonable time," Tammen wrote in his Thursday decision to stay the charges.

He noted that the case involved "extremely serious" charges, but should have been relatively straightforward to prosecute.

"I would add 'miscommunication' and 'inaction' to 'mistakes and missteps' in my assessment of the Crown conduct in this case," Tammen wrote.

DNA linked Doherty to assault

A DNA sample taken from a vaginal swab of the victim linked Doherty to the New Westminster rape, as well as to a series of sexual assaults in Alberta, according to court documents.

Doherty was arrested in Edmonton, where he was charged on May 25, 2011 in four Alberta attacks. His B.C. charges were approved on Oct. 6, 2011 and an arrest warrant was issued the same day.

But he wouldn't appear in court on the B.C. charges until April 20, 2016, a delay that "doomed [the prosecution] from the outset," in Tammen's words. Doherty's trial wasn't scheduled to begin until Dec. 12 of this year.

Tammen described that as a clear infringement of Doherty's rights, as well as those of the victim and the Canadian public.

"The complainant should never have been made to wait seven years for this case to get to trial. The public expects, and rightly so, that a crime such as that alleged here will reach conclusion in a fraction of the time this case has taken," Tammen wrote.

A landmark 2016 Supreme Court of Canada ruling determined that a delay of more than 30 months is an unreasonable infringement of an accused person's right to a speedy trial in a superior court such as B.C. Supreme.

In Doherty's case, Tammen said defence lawyers were responsible for about 13 months of the delay but even subtracting that from the total delay, the wait time still adds up to more than double what's allowed.

'Almost total breakdown in communication'

Doherty is currently serving an 11-year prison sentence for sexually assaulting and threatening four Alberta sex workers. He was convicted of those charges in June 2013 and sentenced a year later.

Crown prosecutors in B.C. argued that they waited to execute the arrest warrant because they didn't want to interfere with Doherty's trial in Alberta.

But Tammen pointed out that there were periods of several months when the accused man had no court dates scheduled and would have been free to make appearances to face the B.C. charges.

Then, after Doherty's conviction, there was "an almost total breakdown in communication between the Crown in the two provinces," Tammen said. In fact, Alberta Crown didn't even notify their B.C. counterparts when Doherty was sentenced.

In the end, the B.C. Crown seemed to be holding out a "fond hope" that Doherty would plead guilty to the New Westminster charges, Tammen said. But Doherty ultimately disagreed with the charges and that hope was lost.