Wis. Stat. § 901.01 Scope
Chapters 901 to 911 govern proceedings in the courts of the state of Wisconsin except as provided in ss. 911.01 and 972.11.
Evidence — general provisions
Wis. Stat. ch. 901
in effectWis. Stat. § 901.02 Purpose and construction
Chapters 901 to 911 shall be construed to secure fairness in administration, elimination of unjustifiable expense and delay, and promotion of growth and development of the law of evidence to the end that the truth may be ascertained and proceedings justly determined.
Wis. Stat. § 901.03 Rulings on evidence
(1) Effect of erroneous ruling. Error may not be predicated upon a ruling which admits or excludes evidence unless a substantial right of the party is affected; and
(a) Objection. In case the ruling is one admitting evidence, a timely objection or motion to strike appears of record, stating the specific ground of objection, if the specific ground was not apparent from the context; or
(b) Offer of proof. In case the ruling is one excluding evidence, the substance of the evidence was made known to the judge by offer or was apparent from the context within which questions were asked.
(2) Record of offer and ruling. The judge may add any other or further statement which shows the character of the evidence, the form in which it was offered, the objection made, and the ruling thereon. The judge may direct the making of an offer in question and answer form.
(3) Hearing of jury. In jury cases, proceedings shall be conducted, to the extent practicable, so as to prevent inadmissible evidence from being suggested to the jury by any means, such as making statements or offers of proof or asking questions in the hearing of the jury.
(4) Plain error. Nothing in this rule precludes taking notice of plain errors affecting substantial rights although they were not brought to the attention of the judge.
Wis. Stat. § 901.04 Preliminary questions
(1) Questions of admissibility generally. Preliminary questions concerning the qualification of a person to be a witness, the existence of a privilege, or the admissibility of evidence shall be determined by the judge, subject to sub. (2) and ss. 971.31 (11) and 972.11 (2). In making the determination the judge is bound by the rules of evidence only with respect to privileges and as provided in s. 901.05.
(2) Relevancy conditioned on fact. When the relevancy of evidence depends upon the fulfillment of a condition of fact, the judge shall admit it upon, or subject to, the introduction of evidence sufficient to support a finding of the fulfillment of the condition.
(3) Hearing out of the presence of a jury. Hearings on any of the following shall be conducted out of the presence of the jury:
(a) Admissibility of confessions.
(b) In actions under s. 940.22, admissibility of evidence of the patient’s or client’s personal or medical history.
(c) In actions under s. 940.225, 948.02, 948.025, 948.051, 948.085, or 948.095, or under s. 940.302 (2), if the court determines that the offense was sexually motivated, as defined in s. 980.01 (5), admissibility of the prior sexual conduct or reputation of a complaining witness.
(cm) Admissibility of evidence specified in s. 972.11 (2) (d).
(d) Any preliminary matter if the interests of justice so requires.
(4) Testimony by accused. The accused does not, by testifying upon a preliminary matter, subject himself or herself to cross-examination as to other issues in the case.
(5) Weight and credibility. This section does not limit the right of a party to introduce before the jury evidence relevant to weight or credibility.
Wis. Stat. § 901.05 Admissibility of certain test results
(1) In this section, “HIV” means any strain of human immunodeficiency virus, which causes acquired immunodeficiency syndrome.
(2) Except as provided in sub. (3), the results of an HIV test, as defined in s. 252.01 (2m), are not admissible during the course of a civil or criminal action or proceeding or an administrative proceeding, as evidence of a person’s character or a trait of his or her character for the purpose of proving that he or she acted in conformity with that character on a particular occasion unless the evidence is admissible under s. 904.04 (1) or 904.05 (2) and unless the following procedures are used:
(a) The court may determine the admissibility of evidence under this section only upon a pretrial motion.
(b) Evidence which is admissible under this section must be determined by the court upon pretrial motion to be material to a fact at issue in the case and of sufficient probative value to outweigh its inflammatory and prejudicial nature before it may be introduced at trial.
(3) The results of a test or tests under s. 938.296 (4) or (5) or 968.38 (4), (5), or (6) and the fact that a person has been ordered to submit to such a test or tests under s. 938.296 (4) or (5) or 968.38 (4), (5), or (6) are not admissible during the course of a civil or criminal action or proceeding or an administrative proceeding.
Wis. Stat. § 901.06 Limited admissibility
When evidence which is admissible as to one party or for one purpose but not admissible as to another party or for another purpose is admitted, the judge, upon request, shall restrict the evidence to its proper scope and instruct the jury accordingly.
Wis. Stat. § 901.07 Remainder of or related writings or statements
When any part of a writing or statement, whether recorded or unrecorded, is introduced by a party, an adverse party may require the party at that time to introduce any other part or any other writing or statement which ought in fairness to be considered contemporaneously with it to provide context or prevent distortion.
Wis. Stat. § 901.08 Admissibility of sexual conduct
(1) In this section:
(a) “Sexual conduct” means any conduct or behavior relating to sexual activities, including prior experience of sexual intercourse or sexual contact, use of contraceptives, and sexual life-style.
(b) “Sexual misconduct” includes a violation of s. 940.22 (2), 940.225 (1), (2), or (3), 940.32, 942.08, 942.09, 942.095, 948.02, 948.025, 948.05 (1) or (1m), 948.055 (1), 948.06, 948.07, 948.072, 948.075, 948.08, 948.081, 948.09, 948.095, 948.10, or 948.11 (2) and includes sexual harassment, as defined in s. 111.32 (13).
(c) “Victim” means a person against whom sexual misconduct allegedly has been committed.
(2) In a civil action involving damages for an injury resulting from sexual misconduct, any evidence concerning a victim’s sexual conduct, opinions of the victim’s sexual conduct, and reputation as to the victim’s sexual conduct, offered to prove that the victim engaged in other sexual conduct or to prove the victim’s sexual predisposition may not be admitted into evidence during the course of any hearing or trial, nor may any reference to such sexual conduct be made in the presence of the jury, except the following:
(a) Evidence of the specific, consensual sexual conduct between the alleged offender and the victim.
(b) Evidence of specific instances of sexual conduct by the alleged victim after an in camera showing by the party requesting the admission that the sexual conduct was the actual cause of the victim’s injury for which damages are requested in the action.
Wis. Stat. § 901.09 Submission of writings; languages other than English
(1) The court may require that a writing in a language other than English offered in evidence be accompanied by a written translation of the writing into English with an attached affidavit by the translator stating his or her qualifications to perform the translation and certifying that the translation is true and correct.
(2) A party may object to all or parts of a translation offered under sub. (1) or to the qualifications of the translator. The court may order a party objecting to all or part of a translation to submit an alternate translation of those parts of the original translation to which the party objects, accompanied by a translator’s affidavit as described in sub. (1). If an objection is made to the qualifications of the translator and the court finds that the translator is not qualified the court may reject the offered translation on that ground alone without requiring an alternative translation by the objecting party.
(3) The court may require a party offering into evidence a translation under sub. (1) or an alternative translation ordered by the court under sub. (2) to bear the cost of the translation.
Wis. Stat. § 901.053 Admissibility of evidence relating to use of protective headgear while operating certain motor vehicles
Evidence of use or nonuse of protective headgear by a person, other than a person required to wear protective headgear under s. 23.33 (3g), 23.335 (8) (a) or (b), or 347.485 (1), who operates or is a passenger on a utility terrain vehicle, as defined in s. 23.33 (1) (ng), a motorcycle, as defined in s. 340.01 (32), an all-terrain vehicle, as defined in s. 340.01 (2g), or a snowmobile, as defined in s. 340.01 (58a), on or off a highway, is not admissible in any civil action for personal injury or property damage. This section does not apply to the introduction of such evidence in a civil action against the manufacturer or producer of the protective headgear arising out of any alleged deficiency or defect in the design or manufacture of the protective headgear or, with respect to such use of protective headgear, in a civil action on the sole issue of whether the protective headgear contributed to the personal injury or property damage incurred by another person.
Wis. Stat. § 901.055 Admissibility of results of dust testing for the presence of lead
The results of a test for the presence of lead in dust are not admissible during the course of a civil or criminal action or proceeding or an administrative proceeding unless the test was conducted by a person certified for this purpose by the department of health services.
Source: WI Statutes (Official Site)URL: https://docs.legis.wisconsin.gov/statutes/statutes/901Fetched: 10/7/2026