Recording Law for Voiceprints & Biometric Data in Wisconsin

Wisconsin allows you to record any conversation in which you are a participant without the other person’s knowledge or consent. This one-party consent rule applies uniformly to in-person conversations, phone calls, and electronic communications such as texts or video calls. The governing statute is Wis. Stat. § 968.31, which prohibits interception of a "wire, electronic or oral communication" unless the person intercepting is a party to the communication or has received prior consent from a party. Wisconsin does not distinguish among media types; the same one-party standard governs all forms of communication covered by the statute. The only statutory exception is when the interception is done "for the purpose of committing any criminal or tortious act," which is a separate legal issue tied directly to the recording act itself.

Wisconsin has no statute that regulates the collection, storage, or use of biometric voiceprints. The only biometric-related provision in state law is Wis. Stat. § 134.98, which is a data-breach notification rule that requires notice if a person’s voiceprint is acquired without authorization in a breach; it imposes no obligations on the collection or processing of voiceprints before any breach occurs. There is no written-consent requirement, no mandated public retention or destruction policy, and no opt-in requirement specific to capturing a voiceprint under current Wisconsin law. In 2025, the legislature considered broader privacy legislation (2025 Senate Bill 166 and Assembly Bill 172) that would have treated biometric data as "sensitive" and required opt-in consent, but both bills failed to pass pursuant to Senate Joint Resolution 1 on March 23, 2026, and are not in force.

Wisconsin’s wiretap statute protects an "oral communication" only if the speaker exhibits an expectation that the communication is not subject to interception under circumstances justifying that expectation. The Wisconsin Supreme Court clarified this standard in State v. Duchow, 2008 WI 57, 310 Wis. 2d 1, 749 N.W.2d 913, adopting a totality-of-the-circumstances test with six non-exclusive factors: (1) the volume of the statements, (2) the proximity of other individuals to the speaker and the potential for the communication to be overheard, (3) the potential for the communication to be reported, (4) actions taken by the speaker to ensure privacy, (5) whether technological enhancement was needed to hear the statements, and (6) the location where the statements were made. If a conversation fails this test — for example, a loud argument on a public sidewalk where others can readily overhear — it may not qualify as a protected "oral communication" under the statute at all. In that event, recording the exchange would not implicate the one-party consent rule because the law does not consider it a protected communication. The same Duchow factors apply to determine whether an utterance is protected, regardless of whether the conversation occurs in person or over a phone or electronic line.

Federal courts covering Wisconsin have held that openly recording on-duty police performing their duties in public is protected by the First Amendment. The controlling precedent is ACLU of Illinois v. Alvarez, 679 F.3d 583 (7th Cir. 2012), which enjoined enforcement of an all-party-consent eavesdropping law against such recording and is binding on Wisconsin as part of the Seventh Circuit. Wisconsin’s own one-party consent rule also permits recording when the civilian is a party to the interaction. The right is not absolute; the Alvarez panel emphasized it does not immunize conduct that obstructs or interferes with police operations. The research notes this is strong Seventh Circuit precedent applicable to Wisconsin but not confirmed by a Wisconsin-specific appellate decision, so it should be treated as persuasive rather than absolute.

Violating Wisconsin’s recording laws carries significant consequences. Under Wis. Stat. § 968.31, unlawful interception is a Class H felony, punishable by a fine of up to $10,000, imprisonment of up to six years, or both, as cross-referenced in Wis. Stat. § 939.50(3)(h). There is also a private right of action under Wis. Stat. § 968.31(2m): anyone whose conversation is illegally recorded may sue for actual damages of at least $100 per day or $1,000, whichever is greater, plus punitive damages and reasonable attorney’s fees. These penalties apply whether the interception occurs in person, over the phone, or via electronic means, and whether the person acting is under color of law or not, except when the recording is done for the purpose of committing any criminal or tortious act.

Imagine you are at a public park and observe two people loudly arguing near the playground. You use your phone to record the exchange because you want to document what happens. Under Wisconsin law, this recording is likely lawful. The argument is loud enough that others nearby can hear it, it is occurring in a genuinely public place, and no one has taken steps to keep it private. Because you are a participant in the conversation, Wisconsin’s one-party consent rule applies. Even if the other person did not know they were being recorded, the law does not require you to inform them. The recording would not violate the wiretap statute because the speakers did not exhibit a reasonable expectation of privacy under the Duchow totality-of-the-circumstances test.

Wisconsin’s wiretap statute, Wis. Stat. § 968.31, prohibits interception of the contents of a "wire, electronic, or oral communication." The statute defines "intercept" as the aural or other acquisition of the contents of such a communication through the use of any device. Silent video-only recording that does not capture audio does not acquire the contents of an oral, wire, or electronic communication as defined, so it falls outside the scope of § 968.31. Separately, Wis. Stat. § 942.08 (invasion of privacy) can restrict the use of a "surveillance device" in narrow circumstances — specifically, installing or using a device in a private place with intent to observe a nude or partially nude person — but it does not impose a general restriction on video recording of disputes, altercations, or police interactions.