Missouri Revised Statutes Title XXXV. Civil Procedure and Limitations § 510.130. Voluntary dismissal--new trial

1. A plaintiff shall be allowed to dismiss his action without prejudice at any time before the same is finally submitted to the jury, or to the court sitting as a jury, or to the court, and not afterward. A plaintiff who has once so dismissed his action and thereafter files another action upon the same claim shall not be allowed to dismiss the same without prejudice after the jury has been impaneled, or after evidence has been introduced in a nonjury case, except

2. No party, who has been granted a dismissal at his request after an adverse ruling of the trial court preventing a recovery on his part, shall as a matter of right be granted more than one new trial or more than one appeal on the ground that the adverse ruling of the trial court preventing a recovery on his part was erroneous.