Last week, the U.S. Supreme Court took away a little more of your right to be free from unlawful police searches. In a 5-3 decision in Utah v. Strieff, the Court held that if the police illegally stop and search you, they can use against you any evidence they find, as long as they determine—after they’ve stopped you—that you’re one of the 7.8 million Americans with an outstanding arrest warrant.

Justice Sonia Sotomayor wrote a fiery and spot-on dissent that forcefully demonstrates the troubling links between racial discrimination, police stops of pedestrians and motorists, arrest warrant databases, and out-of-control police surveillance technologies.

The Strieff Majority Undermined the Exclusionary Rule

In Strieff, a police officer stopped a man coming out of a home he thought might contain “drug activity.” The officer admitted that he had no lawful reason to stop Strieff—he had no reason to believe Strieff had done anything wrong or that Strieff posed a threat to the officer’s safety. Everyone agrees this no-suspicion detention violated the Fourth Amendment’s guarantee of freedom from unreasonable searches and seizures. The officer then ran Strieff’s name through an arrest warrant database and found he had an outstanding warrant for a minor traffic infraction. Using this as justification, the officer arrested Strieff, searched him, and discovered meth in his pocket. Strieff was charged with drug possession.

Generally, courts exclude evidence that the police have found as a result of an unlawful search or seizure like the stop in Strieff, calling it the “fruit of the poisonous tree.” The whole purpose of this is to remove any incentive for the police to search us unlawfully—the theory being that if the police know they won’t be able to introduce evidence of wrongdoing found as the result of an unlawful search—like the drugs found in Strieff’s pocket—they will make sure their detentions and searches meet Fourth Amendment requirements.

But this wasn’t what the Supreme Court did in this case. The Court held Strieff couldn’t invoke the exclusionary rule, reasoning that his outstanding arrest warrant supposedly broke the causal link between the illegal detention and the discovery of contraband.

This is a profoundly disturbing new rule. As Orin Kerr notes: “the majority’s approach practically invites officers to make illegal stops.”

Justice Sotomayor’s Dissent

Justice Sotomayor’s dissent in Strieff persuasively shows that the intervening discovery of an arrest warrant should not be allowed, in her words, to “unspoil the poisonous fruit.” She relies on a century of controlling judicial precedent about the exclusionary rule. Even more importantly, she marshals a host of factual evidence to show that the majority’s decision will aggravate existing racial disparities in our criminal justice system.

Citing to the Brennan Center and Human Rights Watch’s work, she notes “outstanding warrants are surprisingly common.” Powerful police databases contain nearly 8 million arrest warrants, mostly for minor offenses like unpaid parking tickets, traffic violations or violating curfew while on probation, and in many cases these arrest warrants are issued without a judge’s involvement. In some places, a majority of residents have outstanding warrants for their arrest—in Ferguson, Missouri, for example, an astonishing 76% of all residents (16,000 of 21,000) have them.

Police often stop and search people without cause in order to check them for outstanding warrants. For example, during a four-year period in Newark, New Jersey, three-quarters of all pedestrian stops (39,308 of 52,235) included a warrant check. Yet the Department of Justice found 93% of these stops were illegal because they lacked the requisite reasonable suspicion.

These practices disproportionately impact people of color, both because they represent the majority of outstanding arrest warrants and because they are disproportionately stopped on the street. And as Justice Sotomayor notes, the impact for people stopped goes far beyond the mere inconvenience suggested by the term “stop.” The Supreme Court has given police officers “an array of instruments to probe and examine you” during sidewalk and traffic stops. And once an officer arrests you for an outstanding warrant or otherwise, “he can fingerprint you” and “swab DNA from the inside of your mouth.”

Justice Sotomayor’s blistering dissent concludes:

This case tells everyone, white and black, guilty and innocent, that an officer can verify your legal status at any time. It says that your body is subject to invasion while courts excuse the violation of your rights. It implies that you are not a citizen of a democracy but the subject of a carceral state, just waiting to be cataloged.

What the Strieff Decision Teaches Us About Street Level Surveillance

The Strieff decision will only bolster police justification for increasing use of Street Level Surveillance technologies. Once an officer stops you, the Supreme Court has held that they can ask you to identify yourself—and you must do so, if you live in a state with a law requiring you to give the officer your name. The Supreme Court has also held that biometrics are a form of identification. Now, after Strieff, officers can stop you for no reason, collect your fingerprints, iris scan, face image and possibly even your DNA, and, if you have an outstanding arrest warrant, there’s nothing you can do to stop them from using your biometric information against you in court.

As we’ve noted before, police already have access to mobile devices capable of collecting fingerprints, iris scans, and face recognition photographs out in the field. Soon many officers will be able to collect and process DNA out in the field as well. We don’t know much about where the data collected by these devices goes and with whom it’s shared, although we did learn recently from a scathing Government Accountability Office report that much of it is fully accessible to the FBI.

Police use of our biometric information, such as our fingerprints and DNA, raises many problems, including false matches, data breaches, and continuous surveillance. Just last month, EFF and our allies sent a letter to the FBI raising concerns about its Next Generation Identification (NGI) database of facial recognition and other biometric information. We objected that people of color are overrepresented in NGI because of biased police practices, and are more likely than Caucasians to be misidentified through face recognition. We also published a report about the unfair deployment of portable fingerprint readers, DNA collection, and other biometric surveillance against immigrant communities. And, in another EFF report, we condemned the FBI’s ongoing efforts to create tattoo recognition technology that can identify religious iconography.

The Strieff decision suggests that police use of these surveillance technologies will only increase as one of the few legal mechanisms preventing unlawful police stops—the rule excluding evidence discovered during or after the illegal stop—doesn’t apply if the police later discover your name in a massive database of outstanding arrest warrants.

What’s Next?

We need to reform and restrain these and other police surveillance technologies. Perhaps more importantly, we must not adopt any new police surveillance technologies without carefully considering whether the benefits outweigh the costs, and if so, what civil rights and civil liberties protections must be built in at the ground floor.

To do this, we need a transparent and democratic process before government adopts any new surveillance technology. An ordinance requiring this was recently enacted in Santa Clara County in California (the Silicon Valley home of nearly two million people). EFF advocated for this law, along with ACLU and other allies.

During this deliberative process, we must ask whether the proposed new surveillance technology will disproportionately burden people of color. If so, there must be a strong presumption against adopting the technology, even if government officials do not intend to cause this result. A just society should not tolerate such racial disparate impacts.

The Supreme Court majority erred in Strieff. But the rest of us can follow Justice Sotomayor’s lead. When we establish the rules for surveillance technologies and other police practices, we must carefully consider whether we are using our society’s newest tools to perpetuate one of our society’s oldest problems—racial bias.