Every time we interact with computers, smart devices or electronics, we leave detailed trails of our daily experiences. Law enforcement agencies are beginning to grasp the wealth of information new technologies provide, and courts have already made use of data from Fitbits and pacemakers. In Carpenter v United States, the biggest digital security case in decades, the US supreme court was tasked with deciding whether authorities need a warrant to see a person’s cellphone location data.
Last week, in a 5-4 decision authored by Chief Justice John Roberts, the court held that they do.
The Carpenter decision could have sweeping effects on privacy rights in our data-driven age. The case also raises the question of whether and how the law can keep pace with the ever-expanding reach of digital surveillance technology.
Timothy Carpenter was convicted of organizing a series of armed robberies in 2010 and 2011. Carpenter supplied the guns and served as lookout, waiting nearby as other robbers stole hundreds of smartphones from Michigan- and Ohio-based electronics stores. At Carpenter’s trial, prosecutors introduced records taken from his cellphone, which showed his location over five months and revealed that the device was used near each crime scene around the time of the robbery.
The lower court admitted those records, relying on a 38-year-old supreme court decision which held that customers have no expectation of privacy in phone records, and that the police therefore do not need a search warrant to obtain them. Carpenter, found guilty and sentenced to 116 years in prison, appealed.
Under the fourth amendment’s third-party doctrine, law enforcement can compel third-party companies, like cellular carriers, to turn over data from a device. They have several legal avenues to get this type of information: a subpoena, a court order or a search warrant. Each requires an increasing level of detail. For a judge to sign a warrant, police need probable cause to believe the records contain evidence of a crime. In Carpenter, although investigators probably had that evidence, they opted for a court order under the Stored Communications Act. The act imposes a less demanding legal standard, requiring only reasonable grounds to believe the records were “relevant and material to an ongoing investigation”.
The Carpenter case comes down to whether a search warrant is needed before law enforcement can access records that track a person’s minute-by-minute movements. Regardless of the outcome in Carpenter, police and prosecutors can acquire a person’s entire digital history with the appropriate legal process, and as technology evolves, this power continues to grow.
Trial practice is, in large part, about filling in gaps – and, because of technological advancements, data now exist to fill many of those holes. Law enforcement will soon begin investigations by asking: what are the possible data trails? Once prosecutors start introducing this data in court, juries’ expectations will change. To laypeople, electronic information, like other kinds of scientific evidence, comes across as inherently credible. Just as we’ve seen a “CSI effect” – if a case lacks DNA or fingerprints, jurors tend to acquit – we are approaching an “Internet of things effect” on criminal justice.
As Justice Samuel Alito said during the Carpenter arguments: “If you have enough police TV shows where this is shown, then everybody will know about it, just like they know about CSI information.” Jurors will grow accustomed to seeing digital records in court and will come to expect them.
Already, technology is outpacing the law. In 1986, when Congress passed the Stored Communications Act, telecom companies had erected fewer than 2,000 cell site towers across the United States. Neither citizens nor lawmakers were thinking about constant tracking, of digitally recorded crimes or historical cell site location information. Today, more than 300,000 towers carpet the country; over 90% of Americans have cellphones and 70% have smartphones.
“Right now, the court is focused on retroactive tracking, but the technology is already developed for real-time tracking,” says Andrew Ferguson, criminal law professor and author of The Rise of Big Data Policing.
With half the world’s population online, we have entered an age where we are voluntarily self-surveilling all the time. “Before long, real-time facial recognition software will link existing video-surveillance cameras and massive biometric databases to automatically identify people,” Ferguson says.
Data will soon drive the future of criminal justice. In the years since Carpenter’s data was collected, network technology and accuracy has already advanced tremendously. In addition to phone calls, our devices also collect cellular and text message data and record cell site location information, even when the phone checks for updates automatically. Analysts at IHS Technology predict the Internet of Things market will include 30bn connected devices by 2020. Roads will be traveled by smart cars that record everywhere we go and at what speed. Smart homes will show cops where to find an occupant, based on when she turns on a light, uses a smart toothbrush or shifts music from room to room. With this increase in societal data mining comes an increase in surveillance, and more reasons for law enforcement to want it.
In Carpenter, the court has attempted to balance privacy and law enforcement in a digitally developing society. But, the justices rightly pointed out: how are we going to judge sensitivity of information? The court has demonstrated a willingness to protect privacy in the digital age, safeguarding sensitive information – like the contents of phone calls and emails – by requiring a search warrant. Unfortunately, newer technologies have made these earlier warrant protections underinclusive or unenforceable. Now, digital devices collect huge amounts of non-content, yet extremely personal, information, including web browsing histories, Google searches and Uber locations.
The innovations of today set the standards for the future. Although Carpenter involves only cell tower information, the court seemed to peer beyond the facts of the case to broader concerns about how technology is developing. During oral arguments, Alito commented that many Americans don’t realize what information is being collected, or that it even could be. Justice Elena Kagan similarly hinted at the difficulty of determining what a reasonable expectation of privacy is in today’s landscape, where consumers rely on “a new technology that allows for 24/7 tracking”.
Soon thereafter, Justice Stephen Breyer leaned forward in his chair and added that electronic information is infallible. “That’s a big change,” he said, peering down at the gallery through thin glasses. “It’s there in many aspects of life, not just location.”
A cellphone is a metaphor for the newer technologies we rely on – enabling constant tracking with precision that will only continue to grow and collecting information that can be used in unexpected ways. The legal debate around privacy isn’t going away, nor will it be resolved with this one case. But at least the supreme court recognizes the power of these new technologies, and has demonstrated a willingness to confront and limit their dangers.
- Deanna Paul is a former New York City prosecutor