As the town surrounding Fort Detroit grew, DeJean's powers expanded, and he was soon appointed as Judge.
Notably, in 1777 he executed Ann Wyley and a male accomplice for mere theft, in order to set an example to others.
Governor Guy Carleton criticized both DeJean and Hamilton for unjust and illegal acts, and they were both indicted in Montreal for "being tyrannical and acting illegally"[1] Hamilton left Detroit on an expedition to recapture Post Vincennes, South of Detroit along the Wabash River, which had recently declared its support for the Americans.
DeJean, perhaps aware of his precarious legal position without the support of Hamilton, accompanied a convoy of reinforcements.
DeJean was held as a prisoner in Williamsburg for four months,[2] after which time he was paroled because he was considered sympathetic to the American cause.