Dr Jefferies is a lawyer and Laureate Postdoctoral Fellow at the Kaldor Centre for International Refugee Law, ARC Laureate Evacuations Research Hub at the University of New South Wales. She is also an affiliate of the Border Policy Research Institute at Western Washington University. Dr Jefferies specialises in international human rights law and international refugee law, with a focus on transnational legal theory, the law of state responsibility, and the application of international legal norms in transboundary and multi-jurisdictional settings. Her research publications have examined the role of street-level bureaucrats, sub-state entities, and international organisations in the implementation and contestation of international legal norms.

Her current work as part of the ARC Laureate Evacuations Research Hub critically explores international law in relation to the concept of 'evacuations' in a variety of transboundary contexts, including disasters, climate change, conflict, and emergencies.

Dr Jefferies has extensive experience in the practice of asylum and refugee law before United States administrative agencies and the United States federal courts. She holds a PhD from the University of New South Wales; a Master of Studies from the University of Oxford in International Human Rights Law; a Juris Doctorate from Arizona State University; and a Bachelor of Arts in International Affairs from The George Washington University.