California Code, Government Code - GOV § 815

(a) A public entity is not liable for an injury, whether such injury arises out of an act or omission of the public entity or a public employee or any other person.

(b) The liability of a public entity established by this part (commencing with Section 814) is subject to any immunity of the public entity provided by statute, including this part, and is subject to any defenses that would be available to the public entity if it were a private person.