Dubost became a lawyer in 1931.[1] He was appointed as a prosecutor in Pontarlier in 1940.[1] While serving as an assistant prosecutor in Toulon in December 1941, he raised the age of consent to 21 for homosexual men, but not for heterosexual couples.[2]
Dubost joined the French resistance shortly after the Germans invaded.[2] After the war, he was a lawyer at the courts in Aix-en-Provence and Marseille.[1]
Dubost was a member of the French delegation to the Nuremberg trials in 1946.[1] For example, he asked a witness if the Germans had known about the concentration camps.[3] He also presented some documents which showed that Hermann Göring had purposely built camps for British prisoners near RAF targets.[4][5] Moreover, he began research for the prosecution of German businessmen, although the trial was subsequently conducted by United States judges instead.[1]
Dubost worked on prosecutions of collaborationist French businessmen in the late 1940s.[1] He was appointed as assistant to the general prosecutor of the Court of Appeal of Paris in 1955.[1]
