In Texas, the relationship between institutions of county government is designed to be independent and adversarial. In this framework, the principal power of the court is the power of the purse. Each year, the court adopts the county tax rate and the county budget, setting the salary and budget for independent elected officials, as well as outlining expenditures for departments under the direct control of the court. As the administrative head of county government, the court has the authority to enact county-wide policies, and to the extent provided by law, to enact legislation in the form of court orders. The court also exercises varying degrees of oversight over subsidiary county boards and commissioners, which may differ from county to county, but which commonly include drainage districts, irrigation districts, housing authorities and the like. In some instances, the court may also serve as the board of directors for these special districts or authorities, as well as fulfill the role of county school board.