Mo. Rev. Stat. § 209.265: No disclosure of conversation without permission — penalty.

1. An auxiliary aids and services provider or relay agent who is employed to interpret, transliterate or relay a conversation between a person who can hear and a person who is deaf or speech impaired shall not disclose the contents of the conversation, unless the person for whom he interpreted, transliterated or relayed has given written permission for such disclosure.

2. Violation of this section is a class A misdemeanor.