The tale of the earlier courthouses for Decatur County is a saga of damage and destruction by windstorms, fire, and dynamiting by would-be burglars. The county's third courthouse, built in 1875, was a two-story brick Italianate structure, with pavilions on each facade articulated by segmental curved roofs. At the center of the cruciform-plan building was a central open cupola surmounted by a small dome and augmented by high finials at each corner. Because of the damage caused to the building's foundation by the dynamiting of 1877, and also because of a lack of careful repair, the building was finally torn down and replaced by the present building in 1907.
The present courthouse is based upon the Edwardian classical brick-and-stone buildings being erected in England at that time. The design could loosely be termed Georgian Revival, with a touch of the English Arts and Crafts. Its strongest features are the circular eye dormer windows, the central tower with its four clock faces, and the small drum and dome.