Wisconsin Supreme Court Clarifies Digital Privacy Limits in State v. Gasper: What It Means for You

The Supreme Court of Wisconsin has just weighed in on a critical question at the intersection of technology, privacy, and criminal law: when does law enforcement need a warrant to view digital content flagged by private tech companies?

In State v. Gasper, the Supreme Court of Wisconsin ruled that law enforcement did not violate the Fourth Amendment when officers viewed a short video flagged as child sexual abuse material (“CSAM”) by Snapchat, even though no Snapchat employee had ever watched the video themselves.

This decision has major implications for anyone who uses cloud-based platforms, social media, or digital messaging apps.

Let’s break it down.

The Facts: How the Case Began

Snapchat uses automated technology, specifically PhotoDNA (a hash-based scanning tool) to identify known child sexual abuse material uploaded to its platform. In Gasper’s case:

• Snapchat’s software flagged a 16-second video as known child sexual abuse material.
• No Snapchat employee viewed the video.
• Snapchat reported the file to the National Center for Missing and Exploited Children (“NCMEC”), which also relied on hash matching.
• The Wisconsin Department of Justice then viewed the video without a warrant to confirm it was child sexual abuse material.
• Based on that confirmation, law enforcement obtained a warrant, searched Gasper’s devices, and uncovered additional files.

Gasper moved to suppress all evidence, arguing that the first human viewing of the video by law enforcement—without a warrant—violated the Fourth Amendment under Riley v. California and Carpenter v. United States.

The Legal Question: Was This an Illegal Search?

The key issue was not whether the material was illegal; it was whether law enforcement exceeded the scope of a private search when officers viewed the video without a warrant.

The Fourth Amendment protects against unreasonable government searches. But it does not apply to searches conducted by private parties unless the government goes further than the private party already did.

This is known as the private search doctrine. 

The Supreme Court’s Answer: No Fourth Amendment Violation

The Wisconsin Supreme Court held:

• Snapchat’s automated scan was a private search.
• That search frustrated any reasonable expectation of privacy Gasper had in the video.
• When law enforcement later viewed the same video, they did not exceed the scope of the private search.
• Because there was “virtual certainty” the video contained nothing beyond what Snapchat had already identified, no warrant was required to view it.

In short: law enforcement was allowed to confirm what the private technology had already revealed.

The Court emphasized that a private search does not require human eyes—automated scanning technology can qualify.

Why the Court Rejected the Trial Court’s Reasoning

The circuit court initially suppressed the evidence, largely due to concerns about:

• The reliability of hash-based technology (specifically MD5), and
• The fact that no Snapchat employee personally viewed the video.

The Supreme Court firmly rejected both points:

• PhotoDNA is not MD5, and there was no evidence MD5 was even used here.
• There was no proof of unreliability or false positives.
• Whether a person or a program viewed the file first was legally irrelevant.

The Court made clear: what matters is what the private search revealed not who (or what) revealed it.

What This Means for You

This decision has broad implications beyond this case:

1. Tech Platforms Can Trigger Criminal Investigations

If a platform’s automated tools flag content as illegal, that can lawfully kick off a criminal investigation even before a warrant is issued.

2. A Warrant Is Not Always Required at the Earliest Stage

Law enforcement may review content flagged and provided by private companies before seeking a warrant, as long as they do not go beyond what was already identified.

3. Digital Privacy Is Strong—but Not Absolute

The Supreme Court of Wisconsin reaffirmed Riley and Carpenter, but made clear those cases do not shield content once a private actor has already discovered and reported it.

4. These Cases Are Extremely Fact-Specific

Small differences—such as whether police view additional files, access an entire account, or rely on unverified technology—can dramatically change the legal outcome.

Why This Matters in Criminal Defense

Cases involving digital evidence are some of the most complex and fast-evolving in criminal law. Automated scans, CyberTips, and cloud-based evidence raise serious constitutional questions that must be examined case by case.

While State v. Gasper expanded clarity for law enforcement, it does not give police unlimited access to your devices or accounts. The Fourth Amendment still applies and violations still happen.

If You are Under Investigation, Timing and Strategy Matter

Investigations involving digital evidence, CyberTips, and allegations tied to online platforms move quickly and carry life-altering consequences. These cases are complex, highly technical, and emotionally overwhelming for both the accused and their family. 

If you or someone you care about is under investigation or has been charged in a case involving digital content, social media platforms, or alleged possession of illegal material, it is critical to speak with an experienced criminal defense attorney as early as possible. The steps taken at the very beginning of a case can make a significant difference in how the case unfolds. 

Our Attorneys here at Birdsall Muller LLC have experience navigating the legal, technological, and constitutional issues raised in cases like State v. Gasper. We understand what is at stake, and we approach these matters with discretion, diligence, and an unwavering commitment to protecting our clients’ rights. 

Contact us today for a confidential consultation to discuss your situation and learn how we can help.