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BUT THEY DID IT FIRST! The Private Search Doctrine

Americans enjoy the privacy protections afforded them by the 4th Amendment’s right to be free from unlawful, warrantless search and seizure. However, the 4th Amendment only protects against unreasonable searches undertaken by the government or its agents, not private citizens. It does not afford protection against a search initiated by a private person, even one that is unreasonable, unless the private person is acting as an agent of the government or with the participation or knowledge of an officer. So, the 4th Amendment does not protect a person from the computer or phone technician who opens and searches the file labeled “child porn” even though the person told them not to. And once that private search has taken place, the expectation of privacy as it relates to the items searched has been destroyed.  If the private party then reveals the existence of that evidence to police, police can perform a review of that evidence so long as their search of the evidence does not exceed the scope of the search already conducted by the private party.

For example, in United States v. Jacobsen (1984) 466 U.S. 109, employees of a private freight carrier found apparent narcotics during the search of a package. They returned the substance to the package and informed narcotics agents. The agents’ removed the substance from the package and field tested a trace amount of the substance.  The removal of the substance from the package obviously did not exceed the private party’s search.  Did the test? The Court held that although exceeding the scope of the private search, the testing of the trace amount did not invade any reasonable privacy interest and therefore did not constitute a search beyond the scope.

As it relates to computer files, states still differ on how broad the application of the Private Search Doctrine runs, but all seem to agree that if a document or photo has been opened by a private party, an officer can review that file or photo without a warrant. In People v. Wilson, (2020) 56 Cal. App. 5th 128, police opened 4 images they received from NCMEC (the National Center for Missing and Exploited Children) who received the images in a CyberTip from Google. Neither NCMEC nor Google had opened these images in this case, but all 4 images had been reviewed by Google in the past and identified previously as child porn by their matching hash values. So here, the officer’s actions—consisting of opening the electronic files submitted to it by NCMEC and viewing the four images attached to Google’s Cybertip—did not exactly replicate Google’s private actions. The Wilson court set out to determine the degree to which the officer’s additional invasion of Wilson’s privacy exceeded the scope of Google’s private search (the search of his emails against known hash values). Before the officer even received Wilson’s photographs, Google had already reviewed identical images in the past; scanned all of Wilson’s electronic communications to search for content with matching hash values; flagged four of Wilson’s images as matching images Google had previously observed; classified the matching images as depictions of prepubescent minors engaged in sexual acts; forwarded all four images to NCMEC as part of a Cybertip report; and terminated Wilson’s account. The Jacobsen case above explained that, “[t]he Fourth Amendment is implicated only if the authorities use information with respect to which the expectation of privacy has not already been frustrated.” Id. at 117. Because Google’s actions already frustrated any expectation of privacy Wilson possessed in the four photographs at issue, no privacy interest remained in the four images, so no expectation of privacy was violated.  Wilson at 219. Because the assigned hash values, or “digital fingerprints,” are representative of the contents depicted in the photographs themselves, the government gained no new material information by viewing the images. The agent merely confirmed Google’s report that Wilson uploaded content constituting apparent child pornography. Id. at 220.

The Private Search Doctrine does not extend to the warrantless search of homes unless some other exception to the 4th Amendment exists.  So, if the maid enters a home and sees pounds of cocaine, unless some exigency exists, you need to get a search warrant.  The maid’s observations can be used as probable cause for the warrant. However, if a burglar breaks into a house and sees a domestic violence assault taking place, flees and flags down a police officer, exigency would allow the officer to enter the house due to fear of imminent harm to the victim.  This is true even though the burglar illegally entered the home.  Law enforcement can use the evidence discovered by the private party search, whether legally or illegally obtained, as probable cause for a search warrant.

To that end, when evidence is searched or seized in violation of the 4th Amendment, courts will exclude the evidence’s admission at trial to deter future police misconduct. The Private Search Doctrine applies and prevents the exclusion of evidence so long as the private citizen acted without the knowledge, approval, consent, or direction of law enforcement personnel.

What does this mean for you?  Remember to stay within the confines of the private party’s search and you should be fine. Do not direct the private party to expand their search because you will turn an otherwise legal search into a 4th Amendment violation.

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