Wis. Stat. § 751.10: Decisions to be written; part of record; certification.

The supreme court shall decide all cases in writing. One copy of each written decision or opinion delivered by the court or a justice in an action or proceeding in the court shall remain in the office of the clerk of the supreme court and one copy shall constitute a part of the record in the action or proceeding and shall be certified to a court of the United States to which the action or proceeding or record is certified or removed.