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 Oregon, parties to a lawsuit do indeed have the right to voluntarily dismiss their own claims, which is often referred to as a 'nonsuit.' This right is typically absolute and can be exercised at any point during the litigation process until the party has presented all of its evidence at trial, excluding rebuttal evidence. This means that a plaintiff can decide to dismiss their case without prejudice (meaning they could potentially refile the case later) before they rest their case-in-chief. The relevant rules governing voluntary dismissal in Oregon are found in the Oregon Rules of Civil Procedure (ORCP), particularly Rule 54 which outlines the conditions and effects of voluntary dismissal. However, if the defendant has already filed a counterclaim that cannot remain pending for independent adjudication, or if the dismissal would cause some form of legal prejudice to the defendant, the court may deny the right to nonsuit. Additionally, if the case is dismissed after a certain point, it may be with prejudice, which would prevent the plaintiff from refiling the same claim.