Wis. Stat. § 967.01: Title and effective date.

Chapters 967 to 979 may be referred to as the criminal procedure code and shall be interpreted as a unit. Chapters 967 to 979 shall govern all criminal proceedings and is effective on July 1, 1970. Chapters 967 to 979 apply in all prosecutions commenced on or after that date. Prosecutions commenced prior to July 1, 1970, shall be governed by the law existing prior thereto.