Mo. Rev. Stat. § 307.265

The commissioner of this state on the vehicle equipment safety commission shall be the director of revenue who shall serve during his continuance as such officer. The commissioner of this state appointed pursuant to this section may designate an alternate from among the officers and employees of his agency to serve in his place and stead on the vehicle equipment safety commission. Subject to the provisions of the compact and bylaws of the vehicle equipment safety commission, the authority and responsibilities of such alternate shall be as determined by the commissioner designating such alternate.