Mo. Rev. Stat. § 492.510: Questions put to witnesses to be reduced to writing.

If it shall appear to such judge, associate circuit judge or clerk that notice has been given as required by sections 492.420 to 492.590, such officer shall then and there reduce to writing all the questions put to the witnesses by the party desiring such depositions, and also all the questions put by all and every person attending, who shall feel interested, who shall have liberty to examine and cross-examine the witnesses.