This article considers the application of international human rights treaties or conventions to domestic law in common law countries and the historical differences in approach between some jurisdictions. It promotes the view that the judiciary of a country which has signed an international human rights treaty or convention may refer to such a treaty when interpreting domestic law, notwithstanding the fact that the treaty or convention has not been incorporated into domestic legislation. The article also suggests that international human rights treaties and conventions have a role in developing international criminal law and international humanitarian law. It cites the example of the decision that forced marriage is an inhumane act, a crime against humanity, by the Special Court of Sierra Leone, and gives the factual and jurisprudential background to that decision.