Mo. Rev. Stat. § 56.293: To defend elected county officials in certain suits (second, third and fourth class counties).

In addition to all other duties imposed upon the prosecuting attorney in counties of the second, third and fourth classes, if any elected county official be sued in connection with the performance of this office, under the provisions of Section 1983, Title 42, United States Code, the prosecuting attorney shall, if requested to do so by such elected county official, act as defense counsel or co-counsel for such elected official.