The RCMP is set to dramatically expand its review of closed sexual assault cases.

The decision comes after an examination of 2,225 files from 2016 where Mountie investigators had concluded the complainants' allegations were unfounded.

Having identified investigative, supervisory and knowledge gaps, the national police force has decided to re-examine every sexual assault case since 2015 where no charges were laid, no matter the reason.

"We don't have all the file numbers for 2017 yet, but we're expecting something in the vicinity of 25,000 files," Sgt. Wendy Smith told CBC News.

Smith leads the sexual assault review team, which has already expanded from four to 17 members, not including a few other Mounties volunteering to put in some overtime re-examining old cases.

In a report about the 2016 file review, the RCMP said of the 2,225 unfounded cases, officers identified 284 files for further investigation.

The review team found some investigations lacked sufficient documentation explaining how the case was pursued, why it was classified as unfounded, as well as cases where investigators seemed to lack knowledge of consent law.

"During the investigation, not always was a statement taken. That was one issue. Sometimes some of the files or the investigations lacked sufficient supervisory oversight," Smith said.

Training on consent law

The exercise also identified gaps in police training.

"Reviewers noted that some members equated inconsistencies in victims' statements with dishonesty and demonstrated a general lack of awareness regarding how trauma might affect a victim's ability to recount events, or how instinctual and unconscious coping strategies may change or mask emotions," the report says.

Smith said the Mounties will roll out new training for officers on consent case law in early 2018.

Sunny Marriner, executive director of the Ottawa Rape Crisis Centre, said she's pleased the RCMP is expanding its review beyond those allegations deemed "unfounded."

"Really what we're looking at is not case codes. We're looking at practices, and the practices of investigation can occur everywhere, regardless of how the case was closed," she said. "So I'm happy that the RCMP are not limiting themselves to unfounded cases, they need to look at everything that did not move forward to charges."

Advocate case review

Going forward, Marriner said it remains unclear if the RCMP is going to join agencies such as the Ottawa Police Service that have committed to implementing the Philadelphia model of sexual assault case review.

"So in Ottawa, we're using advocate case review, which means that sexual assault centres, rape crisis centres, the people who work with the survivors and the community every day, are also the people bringing a trauma-informed lens to the review of cases," Marriner explained.

Sgt. Smith said the RCMP has not ruled out that approach, including third party reporting for people who aren't ready to talk to the police.

"It allows the victim to obtain support from either victim services or from other advocacy groups until such a time that they feel that they're ready to proceed with an investigation," she said.

The agency involved would send a report to police, which would keep it until the complainant is prepared to move forward.

Standardizing police actions

Police agencies across Canada have been reviewing old cases and committing to new methods of handling sexual assaults since the Globe and Mail published a series of stories that exposed flaws in how officers have handled investigations.

Marriner described it as a "scattershot" approach with no co-ordination among police agencies across the country.

"What I'd like to see is all those different types of policing talking together about implementing best practice models that are similar so that survivors get the same support, treatment and response regardless of where they report in the country," she told CBC News.

That, Marriner suggested, would take leadership at the national level, from the federal ministers of justice and public safety.