Search Warrant Required To Track Suspect Using Cell Phone/Tower Technology

In a landmark decision the United States Supreme Court held that the Fourth Amendment, prohibiting unreasonable searches, required a search warrant by the government to obtain historical cell phone tower records.This may be the most important case of the 2017 Term because it moves the Fourth Amendment from a property rights analysis  to a personal right of privacy.

Consider, as we struggle to reconcile  new technology with the right of privacy,  the words of George Orwell in his masterpiece “1984.”

“It was terribly dangerous to let your thoughts wander when you were in any public place or within range of a telescreen. The smallest thing could give you away. In any case, to wear an improper expression on your face… was itself a punishable offense. There was even a word for it in Newspeak: facecrime…”  
 George Orwell, “1984” – Book One, Chapter V.


Background: The Court started its analysis by reviewing the pervasive scope of the use of cell phone technology by noting that: “There are 396 million cell phone service accounts in the United States—for a Nation of 326 million people.  Cell phones perform their wide and growing variety of functions by connecting to a set of radio antennas called “cell sites.” Although cell sites are usually mounted on a tower, they can also be found on light posts, flagpoles, church steeples, or the sides of buildings.  Cell sites typically have several directional antennas that divide the covered area into sectors.”

“Cell phones continuously scan their environment looking for the best signal, which generally comes from the closest cell site.  Most modern devices, such as smartphones, tap into the wireless network several times a minute whenever their signal is on, even if the owner is not using one of the phone’s features.  Each time the phone connects to a cell site, it generates a time-stamped record known as cell-site location information (CSLI).  The precision of this information depends on the size of the geographic area covered by the cell site.  The greater the concentration of cell sites, the smaller the coverage area, making the location of the cell phone more precise.  As data usage from cell phones has increased, wireless carriers have installed more cell sites to handle the traffic.  That has led to increasingly compact coverage areas, especially in urban areas.”

“Wireless carriers collect and store CSLI for their own business purposes, including finding weak spots in their network and applying “roaming” charges when another carrier routes data through their cell sites.  In addition, wireless carriers often sell aggregated location records to data brokers, without individual identifying information of the sort at issue here.  While carriers have long retained CSLI for the start and end of incoming calls, in recent years phone companies have also collected location information from the transmission of text messages and routine data connections.  Accordingly, modern cell phones generate increasingly vast amounts of increasingly precise CSLI.”

Facts of the Case: Police officer’s arrested four men suspected of robbing a series of Radio Shack and T- Mobile stores in Detroit.  One of the men confessed that, over the previous four months, the group (along with a rotating cast of getaway drivers and lookouts) had robbed nine different stores in Michigan and Ohio.  The suspect identified 15 accomplices who had participated in the heists and gave the FBI some of their cell phone numbers; the FBI then reviewed these call records to identify additional numbers that had called around the time of the robberies.

Based on this information, the prosecutors applied for court orders under the Stored Communications Act to obtain cell phone records for petitioner, Timothy Carpenter and several other suspects.  This statute permits the Government to compel the disclosure of certain telecommunications records when it “offers specific and articulable facts showing that there are reasonable grounds to believe” that the records sought “are relevant and material to an ongoing criminal investigation,” which is less than the probable cause standard to get a search warrant under the Fourth Amendment.

The Federal Magistrate Judges issued orders directing Carpenter’s wireless carriers—MetroPCS and Sprint—to disclose “cell/site sector information for Carpenter’s telephone at call origination and at call termination for incoming and outgoing calls” during the four-month period when the string of robberies occurred. The first order sought 152 days of cell-site records from MetroPCS, which produced records spanning 127 days.  The second order requested seven days of CSLI from Sprint, which produced two days of records covering the period when Carpenter’s phone was “roaming” in northeastern Ohio.  Altogether the Government obtained 12,898 location points cataloging Carpenter’s movements—an average of 101 data points per day.

Carpenter was charged with six counts of robbery and an additional six counts of carrying a firearm during a federal crime of violence.  Prior to trial, Carpenter moved to suppress the cell-site data provided by the wireless carriers.  He argued that the Government’s seizure of the records violated the Fourth Amendment because they had been obtained without a warrant supported by probable cause.  The District Court denied the motion.

At trial, the FBI agent offered expert testimony about the cell site data explaining that each time a cell phone taps into the wireless network, the carrier logs a time-stamped record of the cell site and particular sector that were used.  With this information, the expert produced maps that placed Carpenter’s phone near four of the charged robberies.  In the Government’s view, the location records clinched the case: They confirmed that Carpenter was “right where the . . . robbery was at the exact time of the robbery.” Carpenter was convicted on all but one of the firearm counts and sentenced to more than 100 years in prison.

The Court of Appeals for the Sixth Circuit affirmed holding that Carpenter lacked a reasonable expectation of privacy in the location information collected by the FBI because he had shared that information with his wireless carriers concluding that the resulting business records are not entitled to Fourth Amendment protection. An appeal based on a violation of Carpenter’s Fourth Amendment rights was taken to the United States Supreme Court.

Opinion: The question before the Court was how to apply the Fourth Amendment to a new phenomenon: the ability to chronicle a person’s past movements through the record of his or her cell phone signals. Cell phone tracking partakes of many of the qualities of the GPS monitoring the Court considered in Jones, where it held GPS tracking of a vehicle by attaching the device to the underside of the vehicle without a search warrant, which detailed, encyclopedic, and effortlessly record collecting violated the Fourth Amendment against unreasonable searches. In the Jones case, the majority opinion written by Justice Scalia considered the installation of a GPS tracker, as a trespass based upon a property analysis.  In the Jones case, Justice Sotomayor, concurred in the majority opinion noting however that the property right theory adopted by Justice Scalia was insufficient to deal with the advancement of technology and its ability to intrude in our lives where we had a reasonable expectation of privacy. Chief Justice Roberts recognized this concern as follows:

Mapping a cell phone’s location over the course of 127 days provides an all-encompassing record of the holder’s whereabouts.  As with GPS information, the time-stamped data provides an intimate window into a person’s life, revealing not only his particular movements, but through them his “familial, political, professional, religious, and sexual associations.”

Chief Justice Roberts further noted that: “Cell-site records present even greater privacy concerns than the GPS monitoring of a vehicle we considered in Jones.  Unlike the bugged container in Knotts or the car in Jones, a cell phone—almost a “feature of human anatomy,”

In addition, when individuals leave their vehicle cell phone customers compulsively carry their cell phone with them making the technology even more intrusive than the geo-tracking, which the court found to be in violation of the Fourth Amendment in the Jones case.  Therefore, the Court found that the use of cell phone/tower technology, to track the movements of a suspect, required a search warrant under the Fourth Amendment. Carpenter v. United States, (U. S. 16–402, 06/22/18)

Comment Howard: This case is incredibly important with respect to searches and seizures under the Fourth Amendment using modern technology to track individuals.  Your police officers and department policies should be immediately updated with respect to training.  Since Justice Kennedy just announced his retirement it is worth noting that he voted with the dissent, which strongly suggests that his opinion will survive the appointment of a new Justice to the Supreme Court, even though there was a vigorous dissent by four of the Justices.

Other Posts that may be of interest.

Police Cannot Search Cell Phone Without A Warrant – Aug 6, 2014 7:41 AM

Search Warrant Not Required to Search Abandoned Cell Phone

Can the Police Search a Magnetic Tape on the Back of a Credit, Gift or Debit Card Without Obtaining a Search Warrant? – Dec 12, 2016 2:03 PM

No Search Warrant Required to Search Cell Phone if There Are Exigent Circumstances

Search and Seizure In World Without Walls Feb 7, 2012 11:07 AM  


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