Mo. Rev. Stat. § 229.222
The governing assembly of any county, city, or village of this state may designate any street, road, or highway within such county, city, or village as a memorial road for any law enforcement officer who is killed in the line of duty. Any county, city, or village designating a memorial road pursuant to this section shall provide for and shall be responsible for the costs, erection, and maintenance of any signs marking the designated road.
(L. 2002 H.B. 2039)