The woman, then 17, is now suing the authorities for C$400,000 (S$428,000), reported Canada's CBC News.
The lawsuit, which names the officer involved, local police and the regional government, alleges "a serious lack of professionalism and gross negligence."
The incident, which took place in September 2011, occurred when the police removed the woman, who had been drinking while visiting relatives, from a home in Tasiujaq.
According to civil lawsuit documents filed at Quebec Superior Court, the teenager was handcuffed and put in the back of a police car with a man who had been
arrested earlier for causing a disturbance.
The man, Joe Kritik, who had already been convicted of four sexual assaults and was listed on the sexual offender registry, was not handcuffed.
The lone police officer responsible, who had been on the job for less than a month, left the two in the back of the car while she gathered details about the young woman from the complainant.
She returned and found Kritik with his trousers down on top of the teenager.
She testified in court that she was sexually assaulted.
"The plaintiff was unable to defend herself, being handcuffed in her back and unable to leave the vehicle, the doors being locked," the lawsuit claims.
The officer opened the door and pulled Kritik off the victim.
The woman said she has suffered post-traumatic stress since the attack.
The lawsuit also states the officer's actions "show an incredible lack of concern for the safety of the plaintiff".
Neither the Kativik regional government nor the police force will comment on the events, citing the court case.
This article was first published on Feb 3, 2015.
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