Johan Olaus Søhr MVO (né Sørensen; 6 September 1867 – 1 January 1949) was a Norwegian jurist and police officer.

He studied at the Norwegian Military Academy, and then Law at the University of Kristiania, graduating as cand.jur.

[2] During World War I he was responsible for the investigation of several espionage cases.

[1] Among these were the Otto von Rosen case, which involved confiscation of explosives, bottles with the toxin curare, and anthrax bacteria,[3] and the Rautenfels case, when 188 kg of explosives were confiscated at the railway station Oslo Ø.

Fra opdagelsespolitiets arbeide under verdenskrigen, an account of the espionage cases during World War I.