Wisconsin § 805.18 - Mistakes and omissions; harmless error.

§ 805.18. Mistakes and omissions; harmless error.

805.18(1) (1) The court shall, in every stage of an action, disregard any error or defect in the pleadings or proceedings which shall not affect the substantial rights of the adverse party. 805.18(2) (2) No judgment shall be reversed or set aside or new trial granted in any action or proceeding on the ground of selection or misdirection of the jury, or the improper admission of evidence, or for error as to any matter of pleading or procedure, unless in the opinion of the court to which the application is made, after an examination of the entire action or proceeding, it shall appear that the error complained of has affected the substantial rights of the party seeking to reverse or set aside the judgment, or to secure a new trial. 805.18 History History: Sup. Ct. Order, 67 Wis. 2d 585, 714 (1975); Sup. Ct. Order No. 96-08 , 207 Wis. 2d xv (1997). 805.18 Annotation For an error to “affect the substantial rights” of a party, there must be a reasonable possibility that the error contributed to the outcome of the action. A reasonable possibility of a different outcome is a possibility sufficient to undermine confidence in the outcome. If the error at issue is not sufficient to undermine the reviewing court’s confidence in the outcome of the proceeding, the error is harmless. Evelyn C.R. v. Tykila S., 2001 WI 110 , 246 Wis. 2d 1 , 629 N.W.2d 768 , 00-1739 . 805.18 Annotation Error is harmless if it is clear beyond a reasonable doubt that a rational jury would have found the defendant guilty absent the error. State v. Harvey, 2002 WI 93 , 254 Wis. 2d 442 , 647 N.W.2d 189 , 00-0541 . 805.18 Annotation Section 971.08 (2), requiring vacation of judgment and permission to withdraw a plea in the event of improper notice of the consequences of the plea on immigration and naturalization, is subject to harmless error analysis under this section and s. 971.26. Douangmala , 2002 WI 62 , was objectively wrong because it failed to properly consider the harmless error statutes, this section and s. 971.26, and is thus overruled. The mandatory “shall” in s. 971.08 (2) did not control when both of the harmless error savings statutes also use the mandatory “shall” language. This section and ss. 971.08 (2) and 971.26 are most comprehensibly harmonized by applying harmless error analysis. All of the relevant statutes use “shall,” and, accordingly, none is “more mandatory” than any other. State v. Reyes Fuerte, 2017 WI 104 , 378 Wis. 2d 504 , 904 N.W.2d 773 , 15-2041 . Down Down /statutes/statutes/805 true statutes /statutes/statutes/805/18 Chs. 801-847, Civil Procedure statutes/805.18 statutes/805.18 section true Menu » Statutes Related » Statutes » Chapter 805 × Details for PDF view Link (Permanent link) Bookmark this location View toggle Go to top of document Search in this chapter Search in this section Search in this agency Search in this chapter group Search in this chapter Search in this section Cross references for section Acts affecting this section References to this 1970 Statutes Annotations Appellate Court Citations Administrative Code Index Reference lines Clear highlighting 2023-24 Wisconsin Statutes updated through 2025 Wis. Act 247 and through all Supreme Court Orders and Controlled Substances Board Orders filed before and in effect on August 5, 2026. Published and certified under s. 35.18. Changes effective after August 5, 2026, are designated by NOTES. (Published 8-5-26)