Mo. Rev. Stat. § 532.160: Officer to obey writ, whether directed to him or not.

It shall be the duty of every officer and other person upon whom a writ of habeas corpus shall be served, according to the provisions of this chapter, whether such writ be directed to him or not, to obey and return such writ, according to the exigency thereof, to the court or associate circuit judge by whom the writ was awarded; or, in case of the adjournment of such court, or the absence of such associate circuit judge, then before some other judge herein authorized to issue such writ.