The Supreme Court is expected today to clarify the limits of Canada's rape-shield law.
At issue is just how far the law should go in protecting sexual-assault complainants from scrutiny of their sex lives.
In the case before the top court, a man was initially convicted of sexually assaulting and impregnating a teenager.
Ontario's Appeal Court quashed the verdict on appeal.
It found the trial judge had blocked the defence from asking the complainant relevant questions about her sexual activities.
That made it impossible for the accused to show someone else might have made the teen pregnant.