A judgment is void if the rendering court lacks jurisdiction in the “fundamental sense” (i.e., the court lacks “authority over the subject matter or the parties”). (People v. American Contractors Indemnity Co. (2004) 33 Cal.4th 653, 660; see also Lee v. An (2008) 168 Cal.App.4th 558, 563 [“Lack of jurisdiction in its most fundamental or strict sense means an entire absence or power to hear or determine the case, an absence of authority over the subject matter or the parties.”].)
For example, a judgment is void for lack of personal jurisdiction (one of the two aspects of fundamental jurisdiction) if rendered without proper service of process on the defendant and in the absence of a voluntary appearance or waiver by that defendant. (See, e.g., County of San Diego v. Gorham (2010) 186 Cal.App.4th 1215.) A judgment is void for lack of subject matter jurisdiction if the rendering body had no authority to decide the case or matter before it. (See, e.g., Andrews v. Superior Court (1946) 29 Cal.2d 208 [holding that a “police court” that was established by the charter of the city did not have jurisdiction to enter judgment on a criminal offense].)
By contrast, “[w]hen a court has fundamental jurisdiction, but acts in excess of its jurisdiction, its act or judgment is merely voidable.” (Torjesen v. Mansdorf (2016) 1 Cal.App.5th 111, 117.) For example, a court acts in excess of its jurisdiction where, “though the court has jurisdiction over the subject matter and the parties in the fundamental sense, it has no ‘jurisdiction’ (or power) to act except in a particular manner, or to give certain kinds of relief, or to act without the occurrence of certain procedural prerequisites.” (Abelleira v. District Court of Appeal (1941) 17 Cal.2d 280, 287.)
As explained by the court in Jo Redland Trust, U.A.D. 4-6-05 v. CIT BANK, N.A. (2023) 92 Cal.App.5th 142:
It has been repeatedly declared that the absence of a guardian or conservator for a minor or person lacking legal capacity is only an `irregularity’ and not a jurisdictional defect. Because the court has jurisdiction of the subject matter and the parties, the minor or person lacking legal capacity may `waive’ the defect, or may be estopped to attack the judgment. The court, however, has no authority to disregard the statutory requirement, and a judgment so rendered is in excess of its jurisdiction and voidable by the minor. Similarly, the suspended status of corporate powers at the time of filing of action by a corporation does not affect the jurisdiction of the court to proceed and such a suspension after the filing of action . . . but before rendition of judgment likewise does not deprive the court of jurisdiction or render the judgment void and subject to collateral attack after it has become final. Corporate suspension is merely lack of capacity and may be corrected by reinstatement prior to trial.