Alexander has completed his doctorate on party status to armed conflict in international law in 2022. His doctoral research has been supported by a Clarendon scholarship and by a doctoral scholarship of the German National Academic Foundation.
Alexander is a researcher at the Max Planck Institute for Comparative Public Law and International Law in Heidelberg and teaches International Dispute Settlement at Freie Universität Berlin. He has clerked at the Supreme Court of Namibia.
Alexander holds degrees in law from Humboldt-Universität Berlin (First Legal State Examination – Faculty Prize), Université Paris II – Panthéon-Assas (Maîtrise en droit), and the University of Oxford (MJur – Clifford Chance Prize Proxime Accessit; Law Faculty Prize in International Law and Armed Conflict).