Mo. Rev. Stat. § 221.060: Prisoners to have certain privileges.

Every sheriff and jailer, and other person or persons whatsoever, to whose custody or keeping any person or persons shall be committed by virtue of any writ or process, or for any criminal offense, except on conviction for felony, shall make and post reasonable rules for the operation of the jail, and shall permit any such person committed to his care to obtain and use food and bedding at such person's expense within those rules as may be convenient and necessary for the proper operation of the jail or confinement facility.