The RCMP investigation into serial killer Robert Pickton didn't get the attention it deserved, a senior Mountie acknowledged in an email exchange with Vancouver's deputy police chief.

But in the internal emails released this week, RCMP Deputy Commissioner Gary Bass rejects the suggestion that the force "failed."

The RCMP and Vancouver police have come under heavy criticism for their failure to catch Pickton as he hunted sex workers in Vancouver's Downtown Eastside for years before he was caught in 2002. Pickton was later convicted of six counts of second-degree murder, but has been linked to the deaths of as many as 33 women.

A public inquiry beginning later this year will examine what went wrong, but both forces have already conducted internal reviews.

Vancouver police released a 400-page report last year. It admits the force made numerous mistakes but stressed it was the "RCMP's failed pre-2002 investigation" in nearby Port Coquitlam -- where Pickton's pig farm was located and where a woman accused him of attempted murder in 1997 -- that allowed Pickton to continue killing for so long.

The RCMP hasn't released its own review, citing the forthcoming public inquiry, and has yet to respond directly to the criticisms levelled by Vancouver police.

But in the internal emails released this week by the Vancouver police, Bass acknowledges the Mounties made mistakes. The emails, between Bass and Vancouver's Deputy Chief Doug LePard, were made public in response to an access-to-information request.

"Your in-depth analysis certainly shows that this did not get the attention it should have," Bass wrote LePard, the author of the Vancouver police report, on Aug. 25, 2010, a few days after Vancouver police released their report.

"But (where) we are having a difficult time is ascribing this to any person involved at the time. As they say, hindsight is 20-20."

LePard replied: "I really appreciate that you acknowledge a key finding of my review. ... Really, that's all we have been looking for."

The report was highly critical of both police forces, but stressed that Pickton would have been caught sooner had it not been for a series of failures within the Coquitlam RCMP detachment.

In particular, the report said RCMP investigators were slow to act when, in 1998 and 1999, Vancouver police forwarded information that suggested Pickton was responsible for the disappearance of sex workers from the Downtown Eastside.

After the RCMP took over the investigation in 1999, it said there was a period when it lay dormant for months.

The report also said public tips to Vancouver police that were forwarded to the RCMP were ignored, and inexperienced RCMP investigators botched an interview with Pickton in January 2000, turning down an offer to search his farm.

RCMP declined comment Friday.

In his email, Bass doesn't get into the specifics, but does take issue with its characterization of the RCMP.

"I suspect that at the end of the day, where we may still have a gap (is) in the interpretation of the Pickton investigation in terms of whether it either 'failed' or was delayed too long," he wrote.

In 2001, the two forces created a joint task force named Operation Evenhanded to investigate cases of missing women throughout the Lower Mainland, including cases that were linked to Pickton and others that weren't.

LePard made clear in his email that he isn't criticizing that joint task force, but rather the work of Coquitlam RCMP in the years before it was formed.

The forces also appear to disagree over what exactly the RCMP's role was in the late '90s as Pickton emerged as a suspect.

"The current view is that Pickton was a good suspect, among many others," wrote Bass.

LePard took issue with that.

"Just for the record ... Coquitlam (RCMP) wasn't looking at any other suspects at all because their assignment was to investigate the information from various informants, etc., pointing at Pickton for a murder in Coquitlam."

Pickton is currently serving a life sentence in prison for his six murder convictions. Last year the Supreme Court of Canada rejected his appeal for a new trial.

He was originally charged with 26 counts of murder and was expected to face two separate trials. After his convictions were upheld, Crown prosecutors decided not to proceed on the outstanding charges because he is already serving the maximum sentence.

The remains or DNA of 33 women were found on Pickton's farm, and he bragged to police after his arrest that he killed a total of 49.