How Much Can They Watch You? United States Supreme Court Takes Up Landmark Cell-Phone Privacy Case.

On Monday, the United States Supreme Court agreed to hear the case of Carpenter v. United States. Carpenter was convicted on several counts of armed robbery in violation of the Hobbs Act and sentenced to over 100 years in prison. The case centers on what expectations of privacy we as citizens have in information gathered by cell-phone service providers.

A key government witness in the case testified that he obtained cell-site service data which was able to reveal Carpenter’s location as he made and received cell-phone calls. The particular data in issue is less precise than GPS location data, which can approximate an individual's geolocation within 50 meters. Cell-site service data reveals which cell towers were used to connect an individual’s phone calls, and which direction the data was being transmitted. The accuracy of the data can reveal an individual’s location to within one-half to two miles from the particular cell tower. For example, when Carpenter placed a phone call to his accomplices, the stored data revealed he was within one-half to two miles southwest of a particular cell tower, which placed him in the proximity of a Radio Shack store he and his accomplices robbed.

Carpenter moved to suppress the cell-site data because FBI agents obtained the information without a search warrant. The FBI instead relied on the Stored Communications Act, which allows government agents to retrieve stored business records relating to telephone communications upon a showing of “reasonable grounds” and that the records are “relevant and material” to a criminal investigation. This standard is much lower than the “probable cause” required to obtain a search warrant under the Fourth Amendment.

Carpenter’s motion to suppress was denied and the Sixth Circuit Court of Appeals affirmed the denial. Relying heavily on the landmark Smith v. Maryland case, a Supreme Court decision rendered in 1979, the Sixth Circuit held that Carpenter has no expectation of privacy in data stored by third-party businesses used to facilitate phone communications. In Smith, the government used a pen-register device which monitored the phone numbers Smith dialed. The Supreme Court distinguished the stored phone numbers, which did not reveal the content of Smith’s communications, from a wiretap, which would reveal the content of Smith’s conversations. Essentially, citizens have no expectation of privacy in the names and addresses appearing on the front of a mailed envelope because the postal service needs this information to send the letter. Similarly, an individual should have no expectation of privacy in the phone numbers he dials because the phone company needs this information to place the call.

The Smith decision has been the default rule for decades, and has been relied on in countless court opinions to hold search warrants are unnecessary when the information sought is metadata stored by third-parties. The logic in Smith is essentially this: since the individual gives this information to a third-party, he should not object to the same information being obtained by the government. However, many critics believe the Smith holding has outlived its usefulness. While it is true that very little information can be gleaned from an address or a phone number, in the modern digital age, metadata can reveal more about a person than his own conversations can. For example, Target can detect a young woman is pregnant based on the items she purchases before she ever communicates to a third-party she is pregnant. In Carpenter, the government agents did not limit their request for location data to the days of the robberies. They collected almost 13,000 data points over a four month period. This information could reveal the days and locations Carpenter went to church, visited the doctor, visited an attorney, or any other mundane errands.

In a concurring opinion, Circuit Judge Stanch invited the Supreme Court to reevaluate the Smith holding. Bound by precedent, Circuit Judge Stanch agreed that Smith dictates the outcome of the Sixth Circuit’s opinion, but Circuit Judge Stanch believes Smith is no longer relevant in today’s digital age. Indeed, it is a legal fiction that citizens can voluntarily choose to unplug from the digital economy. As information storage grows, and algorithms become more complex, metadata can reveal much more than where our letters are going. It can monitor our location, monitor our health, and even monitor our ideas. A search warrant obtained pursuant to the Fourth Amendment requires law enforcement to state with particularity the location to be searched and the items to be seized. A request for almost 13,000 data points revealing geolocation is much broader than requesting to search the trunk of a car. If law enforcement was required to obtain a warrant, a neutral judge may have limited such a request to the days of the robberies instead of all data stored during a four month period.

Many legal observers believe that the Supreme Court will limit Smith’s usefulness in the digital age. In fact, the Sixth Circuit’s opinion is well reasoned and completely conforms to the Smith holding. Considering the thousands of petitions to the Supreme Court filed every year, it is unlikely the justices would have agreed to hear such a black-and-white case unless the precedential foundation is crumbling. In recent opinions the Supreme Court has reaffirmed Fourth Amendment protections in the digital age. In United States v. Jones, a 2012 opinion, the justices held that law enforcement cannot place a GPS device on a suspect’s car and track him for extended periods without a warrant. Limiting law enforcement’s ability to track an individual using third-party records would be a logical next step.

Although annoying, speed bumps do not prevent us from reaching our destination; they serve to keep innocent bystanders safe. Reinforcing the warrant requirement in the digital age would not hamper law enforcement’s ability to combat crime, but merely places a constitutional speed bump in their path, and keeps innocent citizens safe from unwarranted government intrusion.