Former Conservative cabinet minister and Winnipeg Police Patrol Sgt. Shelly Glover is resigning from the Winnipeg Police Service, calling it a "toxic workplace."

Glover, who was elected as the member of Parliament for St. Boniface in 2008, left federal politics in 2015 and returned to her previous career as a police officer.

"It is with deep sadness I resign from a career that brought me much joy and satisfaction over the years," Glover wrote in a letter to Winnipeg police Chief Danny Smyth dated April 4 of this year, which was obtained by CBC.

"However, the WPS is no longer a healthy environment," Glover wrote.

"As a result, I am moving on to new opportunities hoping that someone will eventually help the good, decent, hardworking employees I leave behind that are suffering in a workplace that lacks accountability and fair treatment for all."

In the letter, the former minister of Canadian heritage writes about an investigation into a respectful workplace complaint she filed herself, which is apparently still under investigation. Glover says in the letter she expects a resolution on the complaint "even though I am no longer in the workplace."

Winnipeg Police Association president Moe Sabourin says the union was made aware of the complaint and provided Glover with advice and support, as it does all members, and is monitoring the process.

Glover's resignation letter alluded, however, to a more systemic issue within the police service.

"I have worked with some tremendous members and civilians who have repeatedly demonstrated professionalism, kindness and a healthy work ethic," Glover wrote to Smyth.

"We are blessed to have them in our midst and I hope for their sake you consider launching a working group or hire an outside evaluation team to change the toxic workplace that is the WPS."

Glover declined to comment on the letter, saying "I have no comment at this time given my employment status with the WPS."

CBC News has also asked for comment from the Winnipeg Police Service, but has not received a response yet.

Glover was an officer with the police service until 2008, when she ran for election and won the riding of St. Boniface for the Conservative Party of Canada.

She was re-elected in 2011, but left politics in 2015 and returned to her job as a police officer.