Sirleaf writes and teaches courses in the areas of criminal law and international law. Sirleaf previously served as a Sharswood Fellow at the University of Pennsylvania Law School, as an assistant professor of law at the University of Baltimore School of Law, and as a lecturer for the International Human Rights Exchange Programme run by Bard College and University of the Witwatersrand, teaching courses in international law, criminal law, human rights and transitional justice. Her work focuses on remedying the accountability and responsibility gaps that exist in international law. Her scholarship focuses on the challenges institutions face in providing redress to survivors of human rights violations. Her current research agenda analyzes the disproportionate distribution of highly-infectious diseases and the role of law in facilitating this result.