Many of these women cited their shaky faith in the justice system as a reason for not reporting a sexual attack to police.
The newly released study provides insight into the experiences and needs of victims amid heightened concern about whether enough is being done to encourage them to come forward.
Allegations of sexual assault against former CBC Radio host Jian Ghomeshi and accusations of harassment involving two Liberal MPs have sparked widespread discussion about how society handles issues of sexual impropriety — particularly violence directed at women.
The study, completed this year by government researcher Melissa Lindsay, was obtained from the Justice Department's research and statistics division under the Access to Information Act.
It involved 114 interviews in 2009 with survivors of child or adult sexual violence in three unnamed cities in different provinces. The research division worked closely with sexual assault centres in the three provinces to develop the 76-item questionnaire and recruit participants.
More than one-third of those who experienced adult sexual assault reported it to the police or had another person do so.
The most common reasons for not reporting were shame and embarrassment, fear of the offender and lack of confidence in the justice system.
"While 53 per cent of participants stated that they were not confident in the police, two-thirds stated that they were not confident in the court process and in the criminal justice system in general," the study says.
Participants cited ongoing, long-term effects of being attacked, including depression, difficulties with trust and forming relationships, and anxiety, fear and stress.
"The trauma is — I mean, it's absolutely unbearable," one victim told the researchers.
The women described a number of means of coping with effects of the trauma, both positive (such as reading, exercising, writing in a journal) and negative (drug and alcohol abuse, self-harm, suicide attempts).
The women suggested that survivors of sexual violence become informed about the criminal justice system, and know that help is available for victims and that legal proceedings can take a long time. The best way of sharing this information is through school programs and counsellors, they said.
Three broad themes emerged on making improvements — helping survivors feel safe and comfortable, providing them with information on sexual violence and justice procedures, and adjusting the overall system to ensure things like more timely processing of cases and a better balancing of how victim and suspect are treated.
The Conservatives have introduced legislation to create a federal bill of rights for victims aimed at providing them with more information and protection as well as greater opportunities to participate in trials and sentencing.
However, some victims rights advocates have said the legislation falls short because it wouldn't allow people to head to court if they felt their rights were not respected.
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