A permanent county seat was chosen in March 1842 and was located on the north side of the present public square in Carthage. This courthouse was later replaced by a larger two story brick and stone structure that was completed in 1854, which also functioned as the county jail. The courthouse was used as a hospital during the Civil War and was destroyed by fire during fighting in October 1863. Several temporary locations were used for the courthouse over the next 30 years until the current Jasper County Courthouse was constructed on the Carthage square in the mid-1890s..

Following the burning of the courthouse and county jail during the Civil War there was very little left of the original buildings or residents of Carthage. Over the next several months, some former residents returned, but many settled elsewhere – and although the war was itself over, the hostilities among families and former friends were not. Many in Carthage were southern sympathizers, and with a strong federal presence in Missouri, they were reluctant to return. But probably the biggest reason was the simple fear of the lawless bands that roamed the area – there was simply no one to keep them in check.

In the spring of 1865, the state government, eager to restore some degree of normalcy as soon as possible, named three men to the Jasper County Court, and appointed Samuel H. Caldwell as sheriff. In May, these men met in Carthage, likely under the escort of federal troops as no official record of the meeting was kept, did little more than survey the war damage. Nevertheless, the first step of returning order to Carthage and Jasper County had been taken.

The Jasper County jail was the site of a number of hangings with the first being in 1878. On February 15, 1878, the citizens of Carthage witnessed the first legal hanging in Jasper County. John Ables had been brought to Jasper County on a change of venue to be tried for shooting another man in McDonald County. The county court had sentenced him to death. Two stays had been granted, and during his lengthy confinement, he had gained the sympathy, so much so that the day before his scheduled execution, he was allowed to go to Spring River to fish. Finally, there were no more stays, and Ables was hanged from the newly-built gallows on the west side of the county jail. Sheriff J.C. Beamer operated the gallows and was assisted by his aides and the members of the Carthage Light Guard. Public hangings at that time were a major civic event and it was reported that thousands came from all over the region to watch the event.

Subsequent hangings in Jasper County however were conducted behind a framed enclosure and only those receiving a ticket were allowed inside to view the event. The last hangings were the Worden brothers in 1932 and 1933. They were convicted of attacking a Carthage High School girl during a series of road holdups in 1931. Sheriff Oll Rogers directed the construction of an indoor scaffolding system inside the jail for the hanging in 1933, but after that time all executions were moved to Jefferson City and the scaffolding was dismantled.