S.D. Codified Laws § 34-1-20
Hereafter all funds appropriated by the State of South Dakota or otherwise established by the state, or from any other source whatever as a public fund, to be distributed or allotted for any public health program, financed in whole or in part by such public funds or administered or supervised by any public agency controlled by the state or any county, municipality, school district, or other political subdivision, or any corporation or association organized under the laws of the state for the administration of such funds, shall when administered or distributed in payment of services rendered by physicians or licensed chiropractors or optometrists under the provisions of such public health program be so administered or distributed that there shall be no restrictions in the right of any client, officer, employee, or citizen to select any regularly licensed physician, chiropractor, or optometrist of his choice for the performance of services under such program, provided that this section shall in no way affect the provisions of § 34-1-21, relating to the powers and duties of the Department of Health relating to the services for crippled children. This section applies to the purchase of any insurance and any contracts entered into after the effective date of this section with health maintenance organizations, preferred provider organizations and individual practice associations by the State of South Dakota, counties, school districts, and municipalities for health care programs or insurance for public officials or employees. Any violation of this section is a Class 1 misdemeanor.
SDCL 34-1-20