Вот тут несколько публикаций по теме - на мой взгляд, исчерпывающих:
http://www.theglobeandmail.com/news/national/muslim-students-enrolling-in-catholic-schools/article4180638/
https://answers.yahoo.com/question/index?qid=20100311160547AAd5R5S
И вот ещё один комментарий:
Non-catholic students can attend Catholic high schools in Ontario, though there have been some recent fights over whether they can be exempt from religious education requirements. They often are not permitted to attend Catholic elementary schools - whether Jewish, Muslim, Hindu, atheist, or any other non-Catholic persuasion. But sometimes it's allowed. I had several non-Catholic students in my elementary school class growing up, in part I think because it was the only French Immersion program offered in my community at the time. Many other students were baptized but not particularly observant, their parents having chosen the Catholic option not for the religious education but for reasons of school quality or programs offered. Still, it's kind of a weird form of segregation.
As to why separate Catholic education exists, it actually was enshrined in our constitution as a concession to protect the Catholic minority. Catholics are the largest single religious group in Canada, but the majority by far was Protestant, and as in the US, Catholics were a stigmatized minority group in English canada. The public school system was not secular, as it is now, but Protestant. So the publicly funded Catholic school system was enshrined in the constitution as a way to ensure that Catholics weren't discriminated against in education. A real possibility - for instance, in the rural Ontario community where my father was from, they wouldn't allow the Catholic church or school within the city limits. When the mainstream Protestant-based education system became officially secular, the Catholic boards managed to preserve their separateness and their religious character.
As a large unionized employer, affiliated with a large religious voting bloc, they obviously exercise substantial political clout, and so attempts to challenge the legality of Catholic education haven't met with much success so far. On the one hand, it'd seem to violate constitutional principles of equal treatment for religions, but on the other, it's got its own specific provision within our constitution.
As to why separate Catholic education exists, it actually was enshrined in our constitution as a concession to protect the Catholic minority. Catholics are the largest single religious group in Canada, but the majority by far was Protestant, and as in the US, Catholics were a stigmatized minority group in English canada. The public school system was not secular, as it is now, but Protestant. So the publicly funded Catholic school system was enshrined in the constitution as a way to ensure that Catholics weren't discriminated against in education. A real possibility - for instance, in the rural Ontario community where my father was from, they wouldn't allow the Catholic church or school within the city limits. When the mainstream Protestant-based education system became officially secular, the Catholic boards managed to preserve their separateness and their religious character.
As a large unionized employer, affiliated with a large religious voting bloc, they obviously exercise substantial political clout, and so attempts to challenge the legality of Catholic education haven't met with much success so far. On the one hand, it'd seem to violate constitutional principles of equal treatment for religions, but on the other, it's got its own specific provision within our constitution.