Cal. PEN § 632.5

(a) Every person who, maliciously and without the consent of all parties to the communication, intercepts, receives, or assists in intercepting or receiving a communication transmitted between cellular radio telephones or between any cellular radio telephone and a landline telephone shall be punished by a fine not exceeding two thousand five hundred dollars ($2,500), by imprisonment in the county jail not exceeding one year or in the state prison, or by both that fine and imprisonment. If the person has been previously convicted of a violation of this section or Section 631, 632, 632.6, 632.7, or 636, the person shall be punished by a fine not exceeding ten thousand dollars ($10,000), by imprisonment in the county jail not exceeding one year or in the state prison, or by both that fine and imprisonment.

(b) In the following instances, this section shall not apply:

(1) To any public utility engaged in the business of providing communications services and facilities, or to the officers, employees, or agents thereof, where the acts otherwise prohibited are for the purpose of construction, maintenance, conduct, or operation of the services and facilities of the public utility.

(2) To the use of any instrument, equipment, facility, or service furnished and used pursuant to the tariffs of the public utility.

(3) To any telephonic communication system used for communication exclusively within a state, county, city and county, or city correctional facility.

(c) As used in this section and Section 635, “cellular radio telephone” means a wireless telephone authorized by the Federal Communications Commission to operate in the frequency bandwidth reserved for cellular radio telephones.