3, is a landmark decision of the Supreme Court of Canada on the rights of cohabiting same-sex couples to equal treatment under the law.

The court found that the definition of spouse in section 29 of Ontario's Family Law Act, which extended spousal support rights to unmarried cohabiting opposite-sex couples but not same-sex couples, was discriminatory and therefore unconstitutional under section 15 of the Canadian Charter of Rights and Freedoms.

It implies that they are judged to be incapable of forming intimate relationships of economic interdependence as compared to opposite-sex couples, without regard to their actual circumstances.

The section was subsequently amended by the Legislative Assembly of Ontario to include all common-law spouses, whether same-sex or different-sex.

[4] According to R. Douglas Elliott, one of the lawyers in the case, the ruling dealt "a body blow to discrimination" in Canada: "This important decision found that it was constitutionally imperative under the Canadian Charter for laws to provide equal treatment of same-sex common-law couples and opposite-sex common-law couples.