He obtained his diploma from the Recht Hoge School (literally 'High School of Justice') in 1913.
Kusumah Atmadja started his career as a court clerk in 1919 and was seconded to the Court at Buitenzorg (now Bogor). That same year he received a scholarship to continue his legal education at the University of Leiden.
In 1922 he completed his studies. He obtained the title Doctor in de rechtsgeleerheid with a dissertation entitled De Mohamedaansche Vrome Stichtingen in Indië (Institute of Islamic Scholars in the Dutch East Indies), in which he outlined the law of war in the Dutch East Indies.
Judicial career
Upon his return to the Dutch East Indies, Kusumah Atmadja was offered a position as a judge at the Raad Van Justitie (High Court) in Batavia (now Jakarta) After a year, Kusumah Atmadja was appointed Landraad Voorzitter (Chairman of the District Court) in Indramayu.[clarification needed]
He was listed as a High Court Judge in Padang, landraad voorzitter in Semarang, and then a judge in Raad van Justitie in the same city.
When the Japanese occupied the Dutch East Indies, evicting the Dutch, Kusumah Atmadja continued as a court official. In 1942, he served as Chairman of Chihoo Hooin (District Court) in Semarang. In addition, he was also appointed as Chief Justice for Central Java in 1944.