Mass Surveillance and Your Data

What Is Mass Surveillance

Mass surveillance is the collection of information about large numbers of people, most of them suspected of nothing, instead of targeted monitoring of one suspect. Today it rarely means a camera on every corner. It usually means the government getting data that phones, apps, cars, and companies already collect, sometimes with a warrant, sometimes by buying it, and sometimes under laws written for spying on foreigners.

The phrase gets used loosely. Some programs on this page collect data on millions of people. Others start with a single crime and pull in everyone nearby. What they share is that people who did nothing wrong end up in a government file, usually without knowing it.

Protect Your Phone and Your Data

A few settings change what police can get from your phone and how easily. Open the situation closest to yours. None of these steps is illegal, and none requires technical skill.

How a Geofence Warrant Found One Suspect

At about 4:50 p.m. on May 20, 2019, a man walked into a credit union in Midlothian, Virginia, with a note demanding $100,000. He showed a gun, made everyone lie on the floor, and left on foot with $195,000. Security video showed him approaching from a church next door while talking on a cell phone. After that, the trail went cold (Chatrie v. United States).

Three weeks later, police asked a Virginia magistrate for a geofence warrant: an order telling Google to report every phone inside a 150-meter circle around the credit union in the hour around the robbery. The warrant set out three steps, and each one narrowed the list.

Google’s records turned 19 anonymous phones into 3 named people, all from a single warrant.

One of the three was Okello Chatrie. His phone entered the circle about ten minutes before the robbery and headed toward a residential area right after. He was charged, and he argued that the police had searched his data without a valid warrant.

On June 29, 2026, the Supreme Court agreed that getting the data was a search. Writing for the Court, Justice Elena Kagan said Google’s records “serve as a personal journal of a user’s movements,” and that the same logic that protects phone-company records protects them. The Court did not decide whether this warrant was valid. It sent that question back to the appeals court.

Google’s location history was far more precise than the phone-company records the Court protected in 2018.

The 2018 case set the rule the Court built on. In Carpenter v. United States, the government had collected 12,898 location points tracing Timothy Carpenter’s movements over 127 days, without a warrant. The Court ruled 5-4 that police need a warrant for that kind of record. Our 4th Amendment explainer places both cases in the longer line of search rulings.

Geofence warrants grew fast before the Court stepped in.

The counts come from Google’s own report, cited by the Court (Google). Apple, Lyft, Snapchat, and Uber have also received geofence warrants, but Google was “the only one known to respond,” according to the Fourth Circuit. In July 2025, Google began storing location history on users’ phones instead of its servers, and it told the Court it can no longer answer geofence warrants for that data.

The courts had split before the ruling. In August 2024, the Fifth Circuit called geofence warrants unconstitutional “general warrants,” the kind the Fourth Amendment was written to ban, though it kept the evidence because officers relied on the warrant in good faith (United States v. Smith). A Fourth Circuit panel had said getting the data was not a search at all. The Supreme Court settled that part.

What the Government Collects, Tool by Tool

Whether police need a warrant depends less on how much they learn than on how they get it. A warrant is required for your phone’s location records, but not for the same kind of data bought from a broker.

Section 702 After the June 2026 Lapse

Section 702 of the Foreign Intelligence Surveillance Act lets U.S. intelligence agencies collect the communications of foreigners outside the country without an individual warrant, by requiring companies like email and phone providers to hand them over. Congress created it in 2008. The fight over it is about Americans: when a targeted foreigner writes to or calls someone in the U.S., that American’s side of the conversation is collected too, and the FBI can later search it.

Congress extended the program in 2024 for two years. When that ran out in April 2026, lawmakers bought time with short extensions, the last a 45-day extension passed on April 30, by 261-111 in the House and unanimously in the Senate (CNBC). They could not agree on anything longer, and the law lapsed at midnight on June 12, 2026, for the first time since 2008 (NBC News).

The lapse did not stop the collection. The program runs on a yearly approval from the Foreign Intelligence Surveillance Court that, according to NBC News, “does not expire until March 2027,” and legal experts told NBC that those approvals remain valid until they expire. The real deadline for Congress is therefore next spring. The core dispute is whether the FBI should need a warrant before searching the collected data for an American’s name or number.

Buying Data Instead of Getting a Warrant

A warrant is not required to buy what a company is willing to sell. Carpenter and Chatrie limit what police can force a company to hand over. They do not address data that agencies purchase from brokers, who gather location, app, and browsing data from phones and resell it. Some state consumer privacy laws let residents opt out of that sale, and our right to privacy explainer shows which states have one.

In January 2022, a panel of senior advisers to the Director of National Intelligence warned that commercially available data “includes information on nearly everyone” of a kind that “historically could have been obtained, if at all,” only through targeted collection. The same report said it “can be misused to pry into private lives, ruin reputations, and cause emotional distress and threaten the safety of individuals” (ODNI). The report was later declassified. The Fourth Amendment Is Not For Sale Act, which would require a warrant for this kind of purchase, passed the House in April 2024 but did not become law.

What ICE Uses Now

Immigration enforcement is where these tools have grown fastest since 2025. The Department of Homeland Security’s AI inventory, posted in January 2026, listed more than 200 uses of artificial intelligence, up nearly 37% from July 2025. ICE added 25 of them, including three Palantir products and a tool to confirm people’s identities from their faces and fingerprints (FedScoop).

That tool is Mobile Fortify, a phone app agents use in the field. A DHS document says it checks faces against Customs and Border Protection databases, including photos taken when people enter and leave the country (NPR). DHS told NPR in 2026 that the app “does not access open-source material, scrape social media, or rely on publicly available data.” Customs and Border Protection has also signed a contract with Clearview AI, which built its face database from billions of images taken from the internet (NPR).

Other tools reach cars and phones. In May 2025, ICE paid $5 million for a Thomson Reuters subscription that includes “license plate reader data to enhance investigations for potential arrest, seizure and forfeiture,” according to NPR. In August 2025, the administration revived a paused contract with Paragon Solutions, whose Graphite spyware can break into phones. The Citizen Lab found Graphite was used against journalists in Europe earlier that year.

Activists and journalists told NPR in 2026 that during confrontations with immigration officers, agents photographed their faces and license plates, and some later called them by name. ICE’s acting director, Todd Lyons, told Congress there is no database of protesters. Georgetown Law’s Emily Tucker told NPR that even where states cut off DHS’s access to driver data, “they can go to data brokers.”

Where Each Surveillance Power Stands

Two Supreme Court rulings now protect phone location records. Nothing yet limits data the government buys.

Most of the tools used on ordinary people are agency decisions, not laws. That means they can expand or shrink without a vote, and the public often learns about them from contracts, lawsuits, and reporting.

The Honest Disagreement

Serious people disagree about how far these tools should reach.

The case for broad access comes from law enforcement and intelligence officials. A geofence warrant solved an armed robbery that had no other leads. The intelligence community’s own advisers wrote that purchased data “clearly provides intelligence value.” When Section 702 was about to lapse, Senate Majority Leader John Thune said letting it expire would “shut the lights off on this program and put at risk the American people” (NBC News). In dissent in Chatrie, Justice Samuel Alito wrote that the Court “sheds Carpenter’s self-imposed boundaries” and gives people a privacy claim in data they chose to share with a company. Justice Amy Coney Barrett agreed that Chatrie had no reasonable expectation of privacy in data “he voluntarily disclosed to Google.”

The case for limits comes from the Court’s majority, civil-liberties groups, and the same intelligence advisers. The majority wrote that location data lets police reconstruct anyone’s movements “with no real effort,” and that the Fourth Amendment was meant “to place obstacles in the way of a too permeating police surveillance.” The ODNI panel warned that bought data can “pry into private lives.” Groups such as the ACLU and EFF argue that if police cannot force a company to hand data over without a warrant, they should not be able to buy it either.

The two sides narrow on one point. Both accept warrants for targeted searches of a suspect. The disagreement is about data gathered in bulk, before anyone is a suspect.

What the Label Leaves Out

• Most data collection is commercial. Companies gather far more than any agency, mainly for advertising. Government access is the part the Constitution governs.
• Targeted surveillance with a warrant is not mass surveillance. A judge-approved wiretap on one suspect is the system the Fourth Amendment describes.
• Section 702 targets foreigners abroad. Americans are collected when they communicate with those targets, which is why the fight centers on searching that data later.
• Ending one tool rarely ends the practice. Google’s 2025 change stopped geofence warrants for its location history, but other companies hold location data, and brokers sell it.

Frequently Asked Questions

What does mass surveillance mean?

It means collecting information about large numbers of people who are not suspected of anything, instead of watching one suspect. In the U.S. today it usually means government access to data that phones, apps, cars, and companies already collect.

Is Google still doing geofence warrants?

Not for location history. In July 2025, Google began storing that data on users’ phones instead of its servers, and it told the Supreme Court it can no longer respond to geofence warrants for it. Other companies have received geofence warrants.

What is the Supreme Court's ruling on geofence warrants?

In Chatrie v. United States (June 29, 2026), the Court ruled 6-3 that police conduct a Fourth Amendment search when they get a person’s location history from Google. It did not decide whether that warrant was valid and sent the question back to the Fourth Circuit.

Is Section 702 still in effect?

The law lapsed on June 12, 2026, but collection continues under court approvals that run until March 2027. Congress has until then to reauthorize it, change it, or let the program end.

How can I find out what surveillance my local police use?

Start with the Atlas of Surveillance, a searchable database of drones, body cameras, license plate readers, face recognition and other tools used by police across the country. The Electronic Frontier Foundation built it with the University of Nevada, Reno’s journalism school. For anything the Atlas does not list, a public records request to your city or county can ask for contracts and policies.

Can police search my phone without a warrant?

Generally no. In Riley v. California (2014), the Supreme Court ruled that police need a warrant to search the phone of someone they arrest. You can say you do not consent to a search.

What You Can Do

1. Change two settings today. Turn off face or fingerprint unlock before protests and border crossings, and review which apps can see your location. EFF’s Surveillance Self-Defense guides walk through each phone.

2. Ask your city council what surveillance tools police use. License-plate readers and face recognition are usually bought locally. Some cities require public approval before police buy new surveillance technology, under a model the ACLU calls Community Control Over Police Surveillance. If the city will not say, a public records request under your state’s law can get the contracts.

3. Tell your members of Congress where you stand on Section 702 before March 2027. The question is whether the FBI should need a warrant to search Americans’ messages collected under it, and whether agencies should need one to buy your data.

4. Know your rights at protests. Our right to protest page covers what police can and cannot do at a demonstration.