Wis. Stat. § 906.13: Prior statements of witnesses.

(1) Examining witness concerning prior statement. In examining a witness concerning a prior statement made by the witness, whether written or not, the statement need not be shown or its contents disclosed to the witness at that time, but on request the same shall be shown or disclosed to opposing counsel upon the completion of that part of the examination.

(2) Extrinsic evidence of prior inconsistent statement of a witness.

(a) Extrinsic evidence of a prior inconsistent statement by a witness is not admissible unless any of the following is applicable:

1. The witness was so examined while testifying as to give the witness an opportunity to explain or to deny the statement.

2. The witness has not been excused from giving further testimony in the action.

3. The interests of justice otherwise require.

(b) Paragraph (a) does not apply to admissions of a party-opponent as defined in s. 908.01 (4) (b).