|Born||16 August 1893|
|Died||24 April 1945 (aged 51)|
|Cause of death||extrajudicial killing|
|Alma mater||University of Königsberg|
Koch was born in Bartenstein, East Prussia (modern Bartoszyce, Poland), he graduated in law from the University of Königsberg. In 1923, he began working at the Prussian Ministry of Trade and later as the second state commisar of the Berlin stock exchange. In 1927, he opened his own law office. In 1937, he helped win an acquittal for pastor Martin Niemöller.
During World War II, he developed contacts with Claus von Stauffenberg and the 20 July plot conspirators, including Carl Goerdeler. In the 20 July plot, once the Nazis had been routed, Koch was slated to become the presiding judge of the Reichsgericht, the highest court in the German Reich. The plot failed, however, and Koch sheltered one of the conspirators. An informer denounced him and Koch and his family were arrested. He was murdered extrajudicially in Berlin by a Sonderkommando of the SS-Reichssicherheitshauptamt on 24 April 1945.