Every university is responsible for establishing its admission and graduation criteria. It's a matter of academic freedom, which is a recognized principle across Canada and around the world. Currently, no university requires that a student know the second official language upon entry or at graduation. In a number of programs—André mentioned French literature—whether it be business administration, international administration or international trade, the universities will very often require a student to know the other language, English or French, or even a third or fourth language.
At HEC, most students are required to have functional proficiency for the international aspect of administration. They are obviously asked to have very good knowledge of English. The same is true at Ottawa and other universities.