Parties to a lawsuit generally have an absolute right to nonsuit (dismiss) their own claims for relief at any time during the litigation until they have introduced all evidence other than rebuttal evidence at trial.
In Ohio, parties to a lawsuit do have the right to voluntarily dismiss their claims, which is often referred to as a 'nonsuit.' According to Ohio Rules of Civil Procedure, Rule 41(A)(1)(a), a plaintiff may dismiss an action without a court order by filing a notice of dismissal at any time before the opposing party serves either an answer or a motion for summary judgment. Additionally, a plaintiff may dismiss the action by filing a stipulation of dismissal signed by all parties who have appeared in the case. However, if a plaintiff has previously dismissed any federal or state court action based on or including the same claim, a notice of dismissal operates as an adjudication upon the merits, essentially a final judgment against the plaintiff on that claim. Furthermore, once the plaintiff has begun to present their case at trial and has introduced all of their evidence except for rebuttal evidence, the right to a nonsuit without the court's approval is typically lost. At that stage, the court's permission would be required to dismiss the case, and the court may impose terms and conditions as it deems proper.