Wentworth was sworn in as a Justice of the Peace for Van Diemen's Land on 9 September 1830. On 4 October 1830, he led detachments of troops from Bothwell and Hamilton towards the Great Lake and the banks of the Ouse, Shannon and Clyde rivers as part of an operation to "...capture those hostile Tribes of Natives which are daily committing renewed atrocities upon the Settlers..." This occurred as part of what has become known as the Black War in Tasmania.
