Columbia Law School's Sexuality and Gender Law Clinic has filed a friend of the court brief in AAR, a case pending in the Supreme Court of Puerto Rico. The partner of a biological mom was denied a second-parent adoption, and the court will rule on whether same-sex second parent adoption is permissible in Puerto Rico.
The brief is unique (and not only because it was filed in both English and Spanish). Here on the mainland, no litigant has argued a right to second-parent adoption grounded in norms of international human rights. According to the brief, however, Puerto Rico courts regularly incorporate international law and human rights principles into both statutory interpretation and interpretation of the Commonwealth's constitution. The brief surveys the status of second-parent adoption in other countries; considers rulings from such international tribunals as the European Court of Human Rights; and cites to United Nations and other international human rights documents.
According to a blog post about the case, Puerto Rico does allow second-parent adoption by different-sex parents.