Mo. Rev. Stat. § 548.251: Immunity from service of process in certain civil actions.

A person brought into this state by, or after waiver of, extradition based on a criminal charge shall not be subject to service of personal process in civil actions arising out of the same facts as the criminal proceedings to answer which he is being or has been returned, until he has been convicted in the criminal proceeding, or, if acquitted, until he has had reasonable opportunity to return to the state from which he was extradited.