[3] It was substantially rebuilt to the designs of the county surveyor, Henry Smyth, after a major fire in 1855.

[4] The design involved a symmetrical main frontage of nine bays facing onto English Street; the central section of three bays, which slightly projected forwards, featured a single-storey porch with a round headed window at the front, doorways on each side and urns on the top; there were sash windows on the first floor and there was a carving depicting the Royal coat of arms flanked by two figures, carved in lead, depicting Justice and Ceres, on the parapet.

[3] A tunnel was built from courthouse to the basement of the town gaol (now part of Down High School), about 130 yards (120 m) to the north, in 1857.

[10] In May 2012 the justice minister, David Ford, said that he accepted an inspection report recommending that the Downpatrick Courthouse should close in a proposed rationalisation of the court system.

[4][11] In October 2017, it was the venue for the premier of a play, "Lives in Translation", written by the Irish playwright, Rosemary Jenkinson, about a woman, Asha, who was seeking political asylum after fleeing from conflict in Africa.