Complex sentence: Birkmann obtained a doctorate in 1967 in Cologne and served as a judge at the Federal Court in Karlsruhe and in 1991 joined the State Chancellery of the Free State of Thuringia.
Split into simpler sentences: Birkmann obtained a doctorate in 1967 in Cologne and served as a judge at the Federal Court in Karlsruhe. In 1991 he joined the State Chancellery of the Free State of Thuringia.