Warning sex workers in Vancouver's Downtown Eastside that a serial killer may have been stalking the neighbourhood wouldn't have saved women from Robert Pickton, a senior officer within the force told a public inquiry Monday.

A working group within the force was preparing to issue a news release in September 1998 that said police were investigating whether a serial killer was responsible for the murder or disappearance of a "disturbing number of sex trade workers" from the Downtown Eastside, the inquiry heard.

Deputy Chief Doug LePard was put on the defensive when asked to explain why the working group was disbanded after the department decided not to follow its recommendation to issue the news release.

LePard outlined the controversial decision in a critical report issued last year, but he was questioned about it at the inquiry.

He said the head of the force's major crimes section raised concerns the release was "inaccurate" and "inflammatory."

The working group, which had been formed a month earlier to decide how best to investigate reports of missing sex workers, was disbanded.

LePard, who conducted an internal review of the force's handling of the Pickton case, said he doesn't think there would have been anything wrong with sending out the news release.

But he said it likely wouldn't have saved any lives, either.

"People with far more expertise than I have said, 'Look, the women were already aware of it (the serial killer theory), they believed it, but they're so deeply entrenched in their addictions that it just simply doesn't matter,"' LePard said during his first day of testimony.

"When there was rampant publicity about this, there were still women going missing from the Downtown Eastside who turned out to be victims of Pickton."

The force has long been criticized for waiting too long to acknowledge the existence of a serial killer, with officials repeatedly telling reporters there was no evidence to support such a conclusion.

Despite those public denials, it is now clear there was disagreement within the force.

The working group was formed in August 1998 as pressure increased on Vancouver police to put more resources into cases involving missing sex workers.

By then, the force had already received tips implicating Pickton, and Pickton himself had been charged, but never prosecuted, with attempted murder for an attack on a sex worker from Vancouver that was alleged to have occurred at his farm in Port Coquitlam.

The group included Insp. Gary Greer, who at the time was in charge of the district that included the Downtown Eastside, and Det. Insp. Kim Rossmo, a geographic profile who was developing a blueprint for the force's investigation.

Rossmo has been credited as being among the first officers to warn of a serial killer, only to have his warnings ignored.

The pair were preparing to issue a news release on Sept. 30, 1998, that said, in part: "The objective of this group is to determine if a serial murderer is preying upon people in the Downtown Eastside and, if so, what murders and disappearances are linked together."

It would have marked the first time the Vancouver police had publicly acknowledge the possibility of a serial killer, but just two weeks before the news release was scheduled to be issued, the head of the force's major crimes section objected.

"I found the draft news release unacceptable from my standpoint," wrote Insp. Fred Biddlecombe in a memo to Greer. "I found it to be inaccurate and quite inflammatory."

The news release was scrapped and the working group was disbanded. The force's missing-persons unit, which was under the major crimes section, continued to handle the missing women investigations and Rossmo didn't work on the case again until the following year.

LePard identified several possible reasons for Biddlecombe's objections -- primarily that he simply didn't believe the serial killer theory.

"Insp. Biddlecombe, at that time, sincerely did not believe there was foul play going on," said LePard. "Because he believed -- wrongly -- that these women were transient and that they eventually would appear."

LePard interviewed the officers during his review. During those interviews, Rossmo suggested a personality clash between him and Biddlecombe was also a factor, although Biddlecombe denied it.

LePard is the first police witness to testify at the hearings into why police failed to catch Pickton as he murdered sex workers from the Downtown Eastside in the late 1990s and early 2000s.

He authored an internal review of the Pickton investigation for the Vancouver police, which was released publicly last year.

The report is critical of both the Vancouver police and the RCMP in nearby Port Coquitlam, identifying a number of problems with their investigations, including a lack of resources, poor leadership and ineffective communication between forces.

During his testimony, LePard touched on several factors that affected the force's investigation in the years leading up to Pickton's arrest.

There were concerns as far back as the late-1980s that the force's missing-persons unit was poorly structured and understaffed, with just a civilian clerk and a lone officer dedicated to the unit. In 1998, amid concerns about missing sex-trade workers, a second officer was added.

The civilian clerk was the subject of complaints that she was racist, biased towards sex workers, belligerent to families trying to report women missing, and claimed to be a police officer.

LePard has offered a public apology for the police department's failure to catch Pickton, and his report noted that roughly a dozen women disappeared after police first identified Pickton as a suspect in 1997 -- five years before his 2002 arrest.

But the force's lawyers have suggested accepting responsibility is not the same as accepting blame. They've urged commissioner Wally Oppal not to judge investigators with the benefit of hindsight, arguing officers did the best they could with the information they had at the time.

Pickton was eventually convicted of six counts of second-degree murder, though the remains or DNA of 33 women were found at his farm. He claimed he killed 49 women.