A former Scouts Canada leader in Winnipeg is accused of sexually abusing a teenage girl, but charges against him were laid several years after the organization was made aware of concerns about his conduct.

Larry Kiska, 45, was charged in May with sexual assault, sexual exploitation and sexual interference, according to court documents obtained by CBC News.

It is alleged that he repeatedly sexually assaulted the girl, whom he was supervising at the time, in incidents dating back to August 2011.

Scouts Canada confirms that Kiska had served as a volunteer leader from 2007 until 2012, when other leaders started raising concerns about him. He was suspended in June 2012 while officials investigated.

"Specifically, they were concerned about his compliance with our two-scouter rule, and one its key conditions is that a volunteer is never alone with a youth member," said John Petitti, who speaks for Scouts Canada.

"He was seen alone in a vehicle, for example, with scouts."

Terminated for breaking rule

Petitti said officials interviewed Kiska, scouts and other leaders, but nothing criminal was identified at that time.

However, because it was determined that Kiska had broken the rule about being alone with youth members, Scouts Canada terminated its relationship with him in September 2012 and sent a memo to scouts' parents.

"We found nothing to suggest that his actions were criminal in nature. That being said, we hold our volunteers to a very high standard, and the two-scouter rule is one of our most important requirements," he said.

"For us, non-compliance of that rule represents a very high lapse in judgment on the part of the volunteer."

Petitti said it's very concerning that Kiska is now facing sex charges.

"We're, of course, deeply concerned about the impact Mr. Kiska's actions may have had on the victim or victims and their families," he said.

A spokesperson for the Winnipeg Police Service told CBC News the investigation into the matter is closed, and there are no concerns that there may be other victims.

Police are not concerned with how the case was handled by Scouts Canada, the spokesperson added.

Petitti said Scouts Canada vets its volunteer leaders extensively with police record checks, a series of interviews and a complete reference check, as well as a "vulnerable sector screening" process. As well, he said leaders must take training on child abuse safety and sign Scouts Canada's code of conduct.

"We face the same reality as any other national youth-serving organization. We know there are bad people out there who want to betray organizations like ours to harm youth. We simply can't pretend that it doesn't exist," he said.

"So what we do is continually focus on improving our policies to make it all the harder and all the more rare for those who wish to do harm to participate in our organization."

With files from the CBC's Jill Coubrough