(a) The commission of a district may impose an annual tax to be assessed quarterly on all emergency room visits to an institutional health care provider located in the district. In the first year in which the tax is imposed, the tax is assessed on the total number of emergency room visits of an institutional health care provider reported to the Department of State Health Services under Sections 311.032 and 311.033 in the fiscal year ending in 2003. The district shall update this tax basis with the number of emergency room visits reported on a biennial basis.
(b) A tax imposed under this section must be imposed uniformly on each institutional health care provider of emergency room services located in the district. A tax imposed under this section also may not hold harmless any institutional health care provider of emergency room services, as required under 42 U.S.C. § 1396b(w).

(c) The commission shall set the rate of the tax imposed under this section. The rate may not exceed $100 for each emergency room visit.
(d) Subject to the maximum tax rate prescribed by Subsection (c), the commission shall set the rate of the tax at a rate that will generate sufficient revenue to cover the administrative expenses of the district, to fund the nonfederal share of a Medicaid supplemental payment program, and to pay for indigent programs, except that the amount of tax revenue used for administrative expenses of the district in a year may not exceed the lesser of four percent of the total revenue generated from the tax or $20,000.
(e) An institutional health care provider may not add a tax imposed under this section as a surcharge to a patient.