A Nova Scotia board of police commissioners has suspended its police chief after he was charged with one count of sexual assault and two counts of sexual exploitation involving a 17-year-old girl.

Nova Scotia's Serious Incident Response Team announced the charges against John Collyer Thursday morning. The Bridgewater Board of Police Commissioners met Thursday evening and moved to suspend him with pay for 60 days.

"We had planned ahead to this day, should it come, hoping against hope that it didn't. But it did," board chairman Patrick Cappello told CBC News after the meeting.

He said the town council will decide on appointing an interim chief. He praised ​Deputy Chief Scott Feener for providing leadership as SIRT investigated the chief. "We didn't feel we like we were at the head of a foundering ship."

​Collyer was made chief of the Lunenburg County town, which has a population of about 8,500, in 2011, and has served with the force since 1990.

Collyer was placed on administrative leave with pay last August after SIRT received information through the RCMP, and then began its investigation.

SIRT did not detail the nature of that information in a report released Thursday.

Evidence received in late April

The offences are alleged to have happened between April 1 and July 31, 2016. The agency said it interviewed nine civilian witnesses and four police witnesses.

"The investigation included seeking the production of certain documentary evidence from a third party which was not received until the last week of April 2017," said the SIRT report, which does not describe that evidence.

SIRT director Ron MacDonald said he couldn't divulge details on why the disclosure of that evidence took so long.

"It involved some particular legal steps that are not unusual, but are not done every day," he said. "It's just a slow process.… Unfortunately, this is how long it took."

MacDonald said he would not provide any further details so as not to compromise Collyer's right to a fair trial. None of the charges has been tested in court.

When the investigation was announced last year, SIRT also investigated an allegation of obstruction of justice involving Collyer, but MacDonald said he does not expect to lay such a charge in the case.

'It's been a dark day'

The director of Sexual Assault Services for Lunenburg and Queens Counties said she has worked with Collyer on issues relating to sexual assault.

Collyer is scheduled to appear in Bridgewater provincial court on June 14. (Rob Short/CBC)

"He's done so much work around this very issue here in the community," said Dianne Crowell. "This has just got me lost for words, this one. Frankly, John was a colleague and a friend and he did tremendous work, so it's just mind-boggling."

Crowell said Collyer served on several committees to help establish services for those who have experienced sexual assault, including SASLQ itself. He also helped secure a place to store forensic evidence in sexual assault cases for up to five years — at the Bridgewater Police Services building.

While having a police chief charged with sexual assault could cause a chilling effect on reporting of sexual violence to police, Crowell said it's also possible that it could encourage those who have experienced sexual assault to speak up.

"Having these charges brought up against somebody in such a powerful position — the chief of police in a small rural community — hopefully that will … if anything could come from this, it will be that ... even if the person who's being accused of assault is in a very powerful position, it still means something and it may encourage or may embolden others who are experiencing sexual violence to come forward."

Other officers investigated

Over the past five years, SIRT has laid sexual assault charges against two other officers and investigated three or four other cases that did not result in charges, said MacDonald.

"I wouldn't say it's common, but we have laid other charges of sexual assault against police officers," he said. "So it does happen. It's certainly not usual, though."

During the five years ended March 31, SIRT opened 136 investigations, which resulted in 23 charges being laid.

Collyer is scheduled to appear in Bridgewater provincial court on June 14.