He was chair of the Law Department (1913/1914, 1920/1921), university's rector (1932/33), General Secretary of Polish Academy of Learning (1926–39) and its president (1939–1946).
In November 1939 he was arrested by German Nazis during their purge of Kraków's Polish intellectuals (Sonderaktion Krakau).
He became a member of the Committee of Three, which aided persecuted families of persons related to the university; he was also active in underground education.
In 1944 he was involved in the talks that led to the creation of a Provisional Government of National Unity.
His Historia źródeł dawnego prawa polskiego (1925–1926) was reviewed by his former student, another contemporary Polish historian of law and professor of Jagiellonian University, Adam Vetulani, as "the most important support work for historical sciences, created in the interwar period."