The prison closed in 1889 but the building remained in use as a courthouse until the mid-twentieth century, in which time it was also used for some meetings of Argyll County Council.

[2] The original plans for the new building had called for a courthouse and three prisons, one for males, one for females and one for debtors, but the scheme was deemed too expensive and was curtailed.

[1] The new courthouse was designed by James Gillespie Graham based on initial drawings by Robert Reid in the neoclassical style, built in ashlar stone and was completed in 1820.

Internally, the principal room was the main courtroom at the rear of the building on the first floor with views across Loch Fyne.

Police and Justice of the Peace Court hearings continued for a while but, in 1962, Argyll County Council sold the courthouse.