California Penal Code
(a) Every person who, intentionally and without the consent of all parties to a confidential communication, by means of any electronic amplifying or recording device, eavesdrops upon or records the confidential communication, whether the communication is carried on among the parties in the presence of one another or by means of a telegraph, telephone, or other device, except a radio, shall be punished by a fine not exceeding two thousand five hundred dollars ($2,500), or 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 previously been convicted of a violation of this section or Section 631, 632.5, 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) The term “person” includes an individual, business association, partnership, corporation, limited liability company, or other legal entity, and an individual acting or purporting to act for or on behalf of any government or subdivision thereof, whether federal, state, or local, but excludes an individual known by all parties to a confidential communication to be overhearing or recording the communication.
(c) The term “confidential communication” includes any communication carried on in circumstances as may reasonably indicate that any party to the communication desires it to be confined to the parties thereto, but excludes a communication made in a public gathering or in any legislative, judicial, executive or administrative proceeding open to the public, or in any other circumstance in which the parties to the communication may reasonably expect that the communication may be overheard or recorded.
(d) Except as proof in an action or prosecution for violation of this section, no evidence obtained as a result of eavesdropping upon or recording a confidential communication in violation of this section shall be admissible in any judicial, administrative, legislative, or other proceeding.
(e) This section does 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 by this section are for the purpose of construction, maintenance, conduct or operation of the services and facilities of the public utility, or (2) to the use of any instrument, equipment, facility, or service furnished and used pursuant to the tariffs of a public utility, or (3) to any telephonic communication system used for communication exclusively within a state, county, city and county, or city correctional facility.
(f) This section does not apply to the use of hearing aids and similar devices, by persons afflicted with impaired hearing, for the purpose of overcoming the impairment to permit the hearing of sounds ordinarily audible to the human ear.