Karl Otto Koch, the commandant of the Buchenwald concentration camp, is often eclipsed by his decidedly more infamous wife, Ilse Koch. He was Buchenwald's first commandant, and ran the camp from 1937 to 1941. He was transferred, at that point, to the Majdanek camp in Lublin, Poland, due to charges of tax evasion being brought upon him by the local authorities in Weimar.
He was reputed to be an animal lover, and seemed very worried about guards endangering the health of animals in his outdoor gardens. The mindset this reflects, where a deer is considered to have more rights than a human being, need not be expounded upon.
In 1943, Koch was finally arrested (officially) for the murder of two prisoners (a doctor and an orderly, who had treated him for syphilis), and embezzlement. He was executed in 1944, while his wife -- brought up on similar charges regarding the mistreatment of prisoners -- was acquitted.
Hermann Pister succeeded him at Buchenwald, and continued to run the facility until it was liberated.