At its first session in 1804, the Legislative Council of the Territory of Orleans divided the Territory into twelve counties, with New Orleans within the County of Orleans. The same act also established a County Court in each of the twelve counties and authorized Governor William C.C. Claiborne to appoint judges to the County Court benches for terms of four years.

On May 1, 1805 Claiborne selected James Workman to serve as judge in the County of Orleans. The statute also provided for a sheriff, a coroner, a clerk, and a treasurer to complete the staff of each County Court. During its first session, the Territorial Legislature authorized the appointment of attorneys to act on behalf of the Territory, relieving the court clerks of this duty.

The County Courts were given jurisdiction in civil matters involving debts of more than fifty dollars or injuries to persons or property of less than one hundred dollars. The Legislative Council also assigned the County Courts jurisdiction in all non-capital criminal matters; that is, those which could not be punished with death or which were not exclusively within the jurisdiction of a superior court.

In 1806, the Territorial Legislature expanded the jurisdiction of the County Courts, authorizing them to hear all criminal cases brought against slaves, even capital ones. Criminal cases involving slaves were not tried by a jury, but rather by a tribunal consisting of a judge or two justices of the peace and three to five white landowners. In non-capital cases, a single justice of the peace and one or two landowners would suffice. Additionally, territorial law allowed a slaveowner whose slave was executed or incarcerated to seek compensation from the government for the loss of his property.

In 1807, the Territorial Legislature established the City Court to replace the County Court in Orleans Parish. In all other parishes the new courts were called Parish Courts.