International tribunals — Inter-American Court of Human Rights — Jurisdiction — Advisory opinions — Article 64(2) of American Convention on Human Rights, 1969 — Costa Rica seeking advisory opinion as to compatibility of its draft legislation with Article 8(2)(h) of Convention — Legislation not yet in force — Relevance — Method of interpretation of terms of treaty — Whether granting advisory opinion would undermine Court's contentious jurisdiction — Necessity to protect rights of potential victims of human rights violations — Whether request admissible — Whether Court compelled to answer questions posed