Wisconsin Statutes & Annotations
Chapter 909 - Evidence — authentication and identification.
909.015 - General provision; illustrations.

909.015 General provision; illustrations. By way of illustration only, and not by way of limitation, the following are examples of authentication or identification conforming with the requirements of s. 909.01:
(1) Testimony of witness with knowledge. Testimony of a witness with knowledge that a matter is what it is claimed to be.
(2) Nonexpert opinion on handwriting. Nonexpert opinion as to the genuineness of handwriting, based upon familiarity not acquired for purposes of the litigation.
(3) Comparison by trier of fact or expert witness. Comparison by the trier of fact or by expert witnesses with specimens which have been authenticated.
(4) Distinctive characteristics and the like. Appearance, contents, substance, internal patterns, or other distinctive characteristics, taken in conjunction with circumstances.
(5) Voice identification. Identification of a voice, whether heard firsthand or through mechanical or electronic transmission or recording, by opinion based upon hearing the voice at any time under circumstances connecting it with the alleged speaker.
(6) Telephone conversations. Telephone conversations, by evidence that a call was made to the number assigned at the time by the telecommunications company to a particular person or business, if:
(a) In the case of a person, circumstances, including self-identification, show the person answering to be the one called; or
(b) In the case of a business, the call was made to a place of business and the conversation related to business reasonably transacted over the telephone.
(7) Public records or reports. Evidence that a writing authorized by law to be recorded or filed and in fact recorded or filed in a public office, or a purported public record, report, statement, or data compilation, in any form, is from the public office where items of this nature are kept.
(8) Ancient documents or data compilations. Evidence that a document or data compilation, in any form:
(a) Is in a condition that creates no suspicion concerning its authenticity;
(b) Was in a place where it, if authentic, would likely be; and
(c) Has been in existence 20 years or more at the time it is offered.
(9) Process or system. Evidence describing a process or system used to produce a result and showing that the process or system produces an accurate result.
(10) Methods provided by statute or rule. Any method of authentication or identification provided by statute or by other rules adopted by the supreme court.
History: Sup. Ct. Order, 59 Wis. 2d R1, R332 (1973); 1985 a. 297; 1999 a. 85.
Alleged statements of self-identification made in a phone call and in personal contact may not themselves be used to identify the speakers. Nischke v. Farmers & Merchants Bank & Trust, 187 Wis. 2d 96, 522 N.W.2d 542 (Ct. App. 1994).
Tapes are properly identified and authenticated when a party to the recorded conversation identifies the defendant's voice and testifies that the tapes accurately depict the conversation. State v. Curtis, 218 Wis. 2d 550, 582 N.W.2d 409 (Ct. App. 1998), 96-2884.
Authentication can be done through circumstantial evidence. State v. Giacomantonio, 2016 WI App 62, 371 Wis. 2d 452, 885 N.W.2d 394, 15-0968.
Text message authentication is a low standard that can be achieved with the sort of testimonial evidence of a witness with knowledge and circumstantial evidence that was presented in this case. Text and other electronic messages do not require new rules on authentication. State v. Giacomantonio, 2016 WI App 62, 371 Wis. 2d 452, 885 N.W.2d 394, 15-0968.
The circuit court did not err in admitting a copy of a note into evidence under sub. (3). The circuit court, as the trier of fact, inspected the original note, which is self-authenticating under s. 909.02 (9), compared the original and the copy side-by-side, and observed that the copy was identical to the original. Deutsche Bank National Trust Co. v. Wuensch, 2018 WI 35, 380 Wis. 2d 727, 911 N.W.2d 1, 15-0175. See also Federal National Mortgage Ass'n v. Thompson, 2018 WI 57, 381 Wis. 2d 609, 912 N.W.2d 364, 16-1496.
Thinking Outside the “Business Records" Box: Evidentiary Foundations for Computer Records. O'Shea. Wis. Law. Feb. 2008.
Virtual DNA: Whole Device Authentication. O'Shea. Wis. Law. July/Aug. 2019.