He was from 1947 to 1950 Minister of Justice and next 1948-1949 Education Minister of the State of Schleswig -Holstein.
Education and work
Katz, who was originally Jewish, visited the reform school in Kiel. Subsequently, he studied from 1913 to 1919, interrupted by his military service in the First World War, Law, wrote a dissertation on the position of the German Reich President and received his doctorate in this subject. Doctor 's father was Walter Jellinek. From 1924 to 1933 he worked as a lawyer and notary since 1929 in Altona. In 1930 he resigned from the Jewish community because he had moved away from religion as a socialist. As to him in 1933 for racial and political reasons were threatened with arrest, he fled to France on 31 March. The notary was taken from him on June 9, the attorney approval on September 5, 1933. In October 1933 he was a delegate of the League of Nations in Nanjing ( China) and there Advisor to the Government in Municipal Affairs. From 1935 he lived in the United States, where he worked as a scientist at Columbia University and editor of the New York New People newspaper was. This was the newspaper of the German Labour delegation, an organization of social democratic German emigrants. He was also secretary of the " German Labor Delegation in USA " director of "Margin School of Social Science" in New York and director of the magazine The New Leader.
In July 1946, Katz returned to Schleswig -Holstein. In 1951 he became a judge at the Federal Constitutional Court and its Vice- President.
Katz was already in the Weimar Republic, and again after 1945, member of the SPD.
Member of Parliament
1929-1933 Katz was a city councilor in Altona and 1932/33, also City Council President.
On 1 December 1947 he was appointed as Justice Minister in the Prime Minister led by Hermann Lüdemann state government of Schleswig -Holstein. On January 24, 1948 he also took over the leadership of the Ministry of National Education. The formed on August 29, 1949 the Cabinet of Prime Minister Bruno Diekmann he was again exclusively as Minister of Justice. After the state elections in 1950, when the SPD lost its absolute majority, Katz resigned from the state government on 5 September 1950.