The first Texas state constitution of 1845 tried to ameliorate the inflexibility of a single-judge trial court model by also authorizing judges to "exchange benches or hold court for each other when they deem it expedient." Relying on this language, the Legislature enacted a variety of procedural laws over the years to get as close as possible to a "de facto" unified district court in the urban counties that needed multiple district judges, while remaining faithful to the constitutionally mandated structure of single-judge trial courts. However, these procedures are still not as flexible as simply merging all judges in a county into a single district court, and purported failures to properly follow such procedures occasionally result in another basis for appeal.