Mo. Rev. Stat. § 226.080: Salaries, how fixed — veterans' preference authorized.

The salaries of the department heads, engineers, clerks and other employees shall be fixed by the commission, except that the compensation of clerical or other nontechnical employees of the department shall not exceed that of those in similar employment in other departments of the state. Preference shall be given, other conditions being equal, to employment of honorably discharged members of the armed services, but any other preference or discrimination in connection with employment is declared to be unlawful.