Iowa Code § 477.6

Any person employed in transmitting messages by telegraph or telephone must do so with fidelity and without unreasonable delay, and if anyone willfully fails thus to transmit them, or intentionally transmits a message erroneously, or makes known the contents of any message sent or received to any person except the person to whom it is addressed, or such person’s agent or attorney, or willfully and wrongfully takes or receives any telegraph or telephone message, the person is guilty of a simple misdemeanor.