Judicial opinions, or cases, are issued by judges.  Typically, researchers are looking for appellate court opinions that establish and clarify the law in the jurisdiction.  These opinions are readily provided by the Oklahoma courts and various commercial vendors.  Researchers without access to a subscription research service can search the court's website for opinions or use Google Scholar.   

Oklahoma has three appellate courts - Civil, Criminal and Intermediate.  The primary source of court cases and information is Oklahoma State Courts Network.  Additional information about case law research and resources can be found on the Oklahoma Court Decisions research guide.