You have an expectation of privacy in location data that reveals your movements in the physical world, and even short-term surveillance of these movements is a search subject to the Fourth Amendment, the U.S. Supreme Court ruled today in Chatrie v. United States.  

The case involved geofence warrants, a form of dragnet surveillance police have used to vacuum up location data from electronic devices of people who happen to be in the vicinity of a crime. EFF had joined the American Civil Liberties Union, the ACLU of Virginia, and the Center on Privacy & Technology at Georgetown Law in filing an amicus brief in the case. 

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The decision in Chatrie is important: It is the first digital surveillance decision by the Court since its landmark 2018 ruling Carpenter v. United States, which involved prolonged tracking of people’s movements using cell phone location data. The new case expands that ruling by confirming that even shorter-term surveillance of location data can constitute a search because it can still reveal “private matters,” including “a wealth of detail about a person’s familial, political, professional, religious, and sexual associations.”  

The case is also important because the Court also recognized the records generated by the apps on a user’s phone—records we necessarily share with third-party tech company—are a user’s “own” and require Fourth Amendment protection. This is true, regardless of whether those records are “emails, documents, photographs, [ ] calendars” or location data. This will likely have broad implications for data generated by other apps on our phones, even if we click “agree” to sharing that data with third-party tech companies.  

Geofence warrants don’t name a suspect or a specific individual or device the way typical warrants do. Instead, they compel companies—almost always Google—to provide information on every electronic device in a given area during a given time period. This creates a high risk of suspicion falling on innocent people and can reveal sensitive and private information about where individuals have traveled in the past. 

Geofence warrants are the digital equivalent of police going person to person, home to home, without suspicion that any device holder has a connection to a crime. This turns innocent bystanders into suspects, just for being in the wrong place at the wrong time.  

In Chatrie, a 2019 geofence warrant compelled Google to search the accounts of all its hundreds of millions of users to see if any one of them was within a radius police drew around a Northern Virginia crime scene. This area amounted to several football fields in size and encompassed numerous homes, businesses, and a church. 

A federal district court in Virginia in 2022 held that the geofence warrant plainly violated  the Fourth Amendment. If the police want to get information on every device in the area, they must also establish probable cause to search every person in the area, the court said. The judge noted the government lacked particularized probable cause as to every individual within the geofence, which swept up innocent people and covered over 70,000 square meters in a busy area. 

The decision set an important precedent in finding the warrant overbroad and unconstitutional and was later followed by a 2024 federal Fifth Circuit Court of Appeals ruling holding that geofence warrants are “categorically prohibited by the Fourth Amendment.” However, the Chatrie lower court allowed the government to use the evidence it obtained because it relied on the warrant in “good faith.” A much divided en banc panel of the U.S. Court of Appeals for the Fourth Circuit in 2025 affirmed this “good faith” finding in the lower court’s opinion. 

Google in 2023 announced changes to how it stores location data, with the effect of eventually making it impossible for the company to respond to geofence warrants. Since July 2025, mass geofence searches of Google users’ location data have not been possible.  

However, Google is not the only company collecting location data, nor the only way for police to access mass amounts of data on people with no connection to a crime. As we’ve written about extensively, data brokers collect and aggregate location data from many different apps on our phones and provide that data to police. And police can use “cell tower dump” warrants to get access to data on everyone within range of specific cell towers. Suspicionless searches like these drag a net through vast swaths of information in hopes of identifying previously unknown suspects—ensnaring innocent bystanders along the way. 

Chatrie could have wide-ranging implications beyond location data as well. The Supreme Court affirmed that app data is subject to the Fourth Amendment, because users “reasonably view” it as their own and reasonably expect it “to be shielded from the ‘inquisitive eyes’ of the government.” Justice Gorsuch, in an opinion concurring in the judgment, called location data a user’s “personal property,” no different from myriad other “effects” explicitly protected by the text of the Fourth Amendment.  As the Court concluded, “the point of carrying smartphones is to use what is on them,” so the Fourth Amendment has to protect more than just location data generated by the act of carrying the phone itself. 

The Court ultimately did not decide whether the particular warrant at issue in Chatrie was “reasonable” or whether the “good faith” doctrine applied. The case now heads back to the Fourth Circuit Court of Appeals to address these questions.  

But regardless of how the Fourth Circuit rules on remand, this Chatrie opinion will shape how lower courts address police access to location and other data going forward. We look forward to citing Chatrie to press future courts to recognize broad Fourth Amendment protections for user data.

This Pride month, we’re calling on the dating app Grindr to prioritize LGBTQ+ user safety by making privacy the default across its platform. That means no more sharing personal data with advertisers or training AI on private information without users’ opt-in consent.

Grindr is a dating app for the LGBTQ+ community; and for queer people, privacy violations can have life-altering consequences. Information that reveals someone’s sexual orientation, gender identity, or HIV status can be used by employers, governments, family members, scammers, or bad actors to inflict harassment, discrimination, arrest, or violence. For example, data from Grindr and other gay dating apps was sold by data brokers and used to 'out' (the act of disclosing someone's sexual orientation without permission) a gay priest in 2021. 

Despite being the world's most popular gay dating app, Grindr has repeatedly mishandled users' sensitive data. Grindr has been caught sharing users' HIV status and precise location with advertisers without obtaining valid consent, resulting in reprimands and fines in several countries. Its former Chief Privacy Officer even sued, alleging the company fired him for raising concerns about Grindr prioritizing “profit over privacy."

Grindr ended several of its most egregious data sharing practices after they were exposed. But more changes are needed if Grindr wants to earn back trust and prove its commitment to users’ privacy and safety. This Pride month, we’re calling on Grindr to make privacy the default and ensure the immediate implementation of two changes to better protect its users:

Opt Users Out of Behavioral Advertising by Default

Grindr currently allows users to opt out of behavioral advertising, but that protection is not enabled automatically (except in some unspecified regions). As we’ve long warned, behavioral advertising relies on the collection and sharing of personal data across a vast network of advertisers, intermediaries, and data brokers. Once information enters this ecosystem, users have little control over where it goes or how it is used: people’s most private and intimate information can be aggregated, sold, and combined with information from other sources to create detailed personal profiles.

By default, Grindr appears to share data with numerous advertising and tracking companies. Using TrackerControl, an app developed by privacy researcher Konrad Kollnig, we recorded Grindr contacting 20 third-party tracking domains during 15 minutes of app activity (see Grindr_TrackerControl_06-23-2026.csv for exported results). TrackerControl observed Grindr contacting Big Tech companies and ad-tech intermediaries, many of which have faced significant legal scrutiny for privacy violations. Several of these companies auction off ad space through a process called “real-time bidding,” which can expose user data to hundreds of additional companies and be exploited by data brokers. 

The dangers of Grindr’s default settings exposing users’ personal data to this ecosystem are not hypothetical. Between approximately 2017 to 2020, a location data broker collected the precise movements of millions of Grindr users from digital advertising networks and made them available for sale. The commercially available data was allegedly so detailed that, in some cases, it could be used to infer romantic encounters between specific Grindr users. 

Although Grindr has stated that it no longer shares precise location data or profile information with advertisers, it acknowledges sharing other personal data, including mobile advertising identifiers (MAIDs)—unique, persistent device IDs that allow advertising companies and data brokers to connect data about the same individual across different sources. MAIDs are not anonymous, and an entire industry exists to link them to more directly identifying information, like emails and phone numbers. According to Grindr’s privacy policy, companies receiving users’ MAIDs “are aware that such data is being transmitted from Grindr,” which could expose a users’ sexuality to the advertising and data broker ecosystem.

Opt Users Out of AI Training on Personal Data by Default

Grindr should stop training its AI models on users’ personal data without opt-in consent. 

Grindr has been investing heavily in AI features as its CEO strives to make Grindr an “AI-first business.” New AI features include a wingman chatbot, profile recommendations based on users’ inferred “type”, summaries of previous interactions with other users, and AI-generated insights about other profiles (like responsiveness, typical online hours, and engagement patterns). By default, Grindr uses its users’ personal data to train the AI models behind these features.

Grindr claims to never use sensitive health information for AI training and requires users to opt-in to AI training on “special-category” data, which includes chat content and precise location. But Grindr automatically enrolls users in AI training on other private information, including profile photos, age, taps, and display names. Users must navigate several levels of Grindr settings to prevent these personal details from being used to train Grindr’s AI.

AI systems trained on personal data create new privacy risks, including the possibility that personal information may be retained, reproduced, or exposed in unexpected ways. For example, researchers have been able to extract training data from AI systems like ChatGPT.

Beyond AI training, Grindr enables AI-powered features by default and allows both “special-category” data and other personal information to be processed by those features. Even users without access to premium-subscription AI features could have their data automatically used to power those features for other users. “Behavior-based profile insights” (pictured below) could expose information that users would never choose to share publicly, like the types of people they interact with on Grindr, their typical online hours, and how often they initiate conversation with other users.

Image of the “Profile Insights” feature from a Grindr blogpost promoting its premium, AI-first subscription

Regardless of whether new AI features leak private information, users deserve meaningful control over how their personal data is used and by whom. Grindr notifies users that their personal information may be used to train AI and that they can opt out on a separate settings page, but this notice does not specify the type of data used (i.e. profile photos, taps) and it is unlikely that people carefully read or understand it. Closing the notice or clicking its only button (which is “Proceed”) maintains Grindr’s default of using personal information for AI training. To respect users’ autonomy, Grindr should require opt-in consent before training AI models on personal data.

Notice displayed in the Grindr app about the use of personal data for new AI features

Celebrate Pride by Demanding Better Privacy

Grindr must immediately stop prioritizing profits over users’ safety. The ability to opt-out is not an acceptable substitute for opt-in consent, especially given the added risks of data sharing for LGBTQ+ users. Defaults matter—studies show that most people cannot or do not change the default settings of technologies they use.

If Grindr wants to back up its claim that it “takes user privacy very seriously,” it should make privacy the default across its platform, rather than something users need to go through complicated processes to opt in to.