Appeals from superior court judgments in both criminal and civil cases must be decided on the merits of the case based upon the record on appeal. The Courts of Appeal do not hear testimony, retry the case or reconsider the factual findings of the judge or jury. They review the final judgment or appealable order for prejudicial errors of law. Decisions of the Courts of Appeal that determine a cause shall be in writing with the reasons stated. (Cal. Const., Art. VI, § 14)
Courts of Appeal have original jurisdiction in habeas corpus, mandamus, certiorari and prohibition proceedings. In most writ proceedings, the court has discretion whether to decide the merits of the claims set forth in the petition.