Professor Renteln studies international law, human rights, comparative legal systems, Constitutional law and legal and political theory. An expert on cultural rights, including the use of the "cultural defense" in the legal system. Professor Renteln has lectured to judicial organizations and law enforcement groups on this subject. She served on the State Bar Commission on Access to Justice and the California Judicial Council Access and Fairness Advisory Committee. She also served as a member of the California Attorney General's Commission on Hate Crimes.