Prior to June 1998, California's trial courts consisted of Superior and Municipal courts, each with its own jurisdiction and with its number of judges fixed by the Legislature; prior to 1951, the Santa Rosa Justice Court was one of twelve such inferior courts in the County. The Justice Court (also known as the Santa Rosa Justice's Court; more formally designated as the State of California's Justice Court for Santa Rosa), had jurisdiction over the City of Santa Rosa and surrounding area of central Sonoma County, California. The Santa Rosa Justice Court was reorganized in 1952 as part of the State of California's inferior court reorganization program authorized by the voters as California Proposition 3 in 1950, which combined the offices of the township justices of the peace and city police court judges; the Santa Rosa Justice Court and other, local municipal courts were combined as the Santa Rosa Judicial District Court, or more formally, the State of California's Municipal Court for the Santa Rosa Judicial District on Jan. 1, 1952.

A number of other reorganizations and consolidations of the County's District Courts took place over the next four decades until the District Courts and other inferior courts were absorbed into the Superior Court following another voter-authorized reorganization in 1998, California Proposition 220.