Wis. Stat. § 905.015: Interpreters for persons with language difficulties, limited English proficiency, or hearing or speaking impairments.

(1) If an interpreter for a person with a language difficulty, limited English proficiency, as defined in s. 885.38 (1) (b), or a hearing or speaking impairment interprets as an aid to a communication which is privileged by statute, rules adopted by the supreme court, or the U.S. or state constitution, the interpreter may be prevented from disclosing the communication by any person who has a right to claim the privilege. The interpreter may claim the privilege but only on behalf of the person who has the right. The authority of the interpreter to do so is presumed in the absence of evidence to the contrary.

(2) In addition to the privilege under sub. (1), a person who is licensed as an interpreter under s. 440.032 (3) may not disclose any aspect of a confidential communication facilitated by the interpreter unless one of the following conditions applies:

(a) All parties to the confidential communication consent to the disclosure.

(b) A court determines that the disclosure is necessary for the proper administration of justice.