The structure of the judiciary of Texas is laid out in Article 5 of the Constitution of Texas and is further defined by statute, in particular the Texas Government Code and Texas Probate Code. The structure is complex, featuring many layers of courts, numerous instances of overlapping jurisdiction, several differences between counties, as well as an unusual bifurcated appellate system at the top level found in only one other state: Oklahoma. Municipal Courts are the most active courts, with County Courts and District Courts handling most other cases and often sharing the same courthouse.