A female RCMP constable in B.C. is suing a supervisor for allegedly misusing his authority to sexually assault her and force her into an intimate relationship.

In a claim filed in B.C. Supreme Court Aug. 26, Const. Susan Gastaldo, stationed in a Lower Mainland detachment, also claims Vancouver police mishandled an investigation into her allegations.

The federal attorney general and the B.C. solicitor general are also named as defendants in the suit, although the Vancouver police department is not.

Gastaldo was hesitant to file the suit but ultimately decided it was necessary, said her lawyer, Walter Kosteckyj .

"I think she feels it’s something she needs to do not for herself, but for other women who may have been sexually harassed," Kosteckyj said.

Code of conduct hearing

The Vancouver force had been called in as an outside police agency in 2009 to investigate after Gastaldo complained to the RCMP that she had been coerced, threatened and assaulted by the senior officer.

According to Gastaldo’s claim, Vancouver police failed to consider her vulnerability or evidence about inappropriate conduct by the male staff sergeant she has accused.

"She hasn't been able to work, she's under psychological care," Kosteckyj said. "She obviously felt that it was important enough that she had to come forward publicly about it and she's commenced a lawsuit to clear her name and to get justice."

Gastaldo and her superior face an RCMP code of conduct hearing in September.

Kosteckyj represented Robert Dziekanski's mother at an inquiry into his death while in RCMP custody at Vancouver aiport in October 2007. He said Gastaldo isn't the only police officer to contact him since the Dziekanski investigations.

"This is another matter of police investigating themselves and once again it raises some serious questions," said Kosteckyj.

No statements of defence have been filed.

With files from the CBC's Jason Proctor