DOJ Makes Revisions to Cell-Site Simulator Policy and Broadens Warrant Requirements for Cell Phone Surveillance: What Does This Change Mean to You?

The United States Department of Justice's announces that it will begin requiring federal agents to obtain a warrant before using cell-site simulator.

Photo provided by NPR.

In response to an outcry from privacy activist, judges, and concerned citizens, the United States Department of Justice announced revisions to their policy concerning the use of cell-site simulators.  The policy is designed to promote transparency in how the Department of Justice uses cell-site simulators, and comes to the protection of criminal defendants that might have had their data collected illegally.  Federal law enforcement agents and any state agents that are working along federal agents will be affected by the new policy changes.

A cell-site simulator, more commonly known by their brand name “stringray,” is used by law enforcement personnel to mimic a traditional cell phone tower.  Stringrays are manufactured by defense contractor Harris Corporation, and typically sell to law enforcement departments for a base price of $60,000.  Less sophisticated versions can be purchased for around $1,800.  This allows law enforcement departments to track a citizen’s whereabouts, as the citizen’s mobile phone believes the stingray is a cell tower, and sends the stingray a signal with its location and other information used to identify the cell phone.  The devices work by essentially blocking 3G and 4G signals, thereby requiring phones to use the 2G signal which is unsecured.

It seems like [court precedent] makes clear that as long as there is not a physical intrusion onto personal property, the monitoring of cell phone “pings” to towers will not violate the Fourth Amendment.

Following recent Supreme Court cases dealing with GPS or other tracking devices, it seems like the use of cell-site simulators is not a constitutional violation of the Fourth Amendment.  In United States v.  Jones, the Supreme Court unanimously held that law enforcement departments must obtain a warrant in order to install a tracking device on a citizen’s car to comply with the Fourth Amendment’s prohibition on unreasonable searches and seizures.  The Court outlined that the trespass onto Jones’ car itself was not a search, nor was monitoring Jones on public roads a search, but combined, the trespass and monitoring was unreasonable without a warrant under the Fourth Amendment.

Conversely, in United States v.  Skinner, Drug Enforcement Administration (DEA) agents obtained the cell phone number of Skinner through a criminal informant, and used this information to track Mr. Skinner on public roads as Skinner was traveling from Arizona to Tennessee to deliver a large amount of marijuana.  Before using this information the DEA agents did not obtain a search warrant, but only a court order.  The United States Court of Appeals for the Sixth Circuit ruled that Skinner had no expectation of privacy in the information that his cell phone gave out under the Fourth Amendment.  In coming to this determination, the Sixth Circuit noted two differences in the facts and reasoning behind Skinner and Jones: (1) the trespass onto Jones’ private property in order to obtain information; and (2) the monitoring in Skinner only lasted three days, which was much more reasonable than the four weeks’ worth of tracking in Jones.

So, how do cases like Skinner and  Jones relate to the issue of cell-site monitoring?  It seems like the cases make clear that as long as there is not a physical intrusion onto personal property, the monitoring of cell phone “pings” to towers will not violate the Katz test, and therefore do not violate the search warrant requirement of the Fourth Amendment.  However, these devices might still be violating privacy laws, as some cell-site monitoring devices have the power to intercept the contents of text messages and listen to your phone calls. However, the DOJ’s Policy Guidance Report on cell-site monitoring disputes this, and claims that cell-site monitoring devices are not capable of intercepting the content of calls or text messages, as this would be a violation of 18 U.S.C.  § 3127(3), the Pen Register Statute.

Fortunately, the new DOJ policy suggests that the cell-site monitoring devices may only be used in “pen register mode.” According to Attorney Nate Cardozo at the Electronic Frontier Foundation, this will restrict the devices to only “collect only the basic location of the phone and the numbers of incoming and outgoing calls and texts.  Agents will not be allowed to collect the content of your communications—like your emails or text messages—even if the cell-site simulator is capable of such collection.” Among other concerns are the breadth and scope of cell-site devices, the amount of information being collected, the time period that information is being kept, and the action carried out with the information.

Another big concern among privacy activist—knowing what the DOJ is doing with the information it receives from both the targeted and untargeted devices.  In their new policy, the DOJ requires cell-site simulator operates to delete date as soon as a known cellular device is located, and no less than once daily.  For unknown devices, all data must be deleted as soon as the targeted devices are located and at least once every 30 days.  When the cell-site simulator is going to be used to track a new suspect, the device must be cleared of all previous data.

[The warrant requirement] will add a serious layer of protection for citizens, which the Supreme Court seemed reluctant to do based on their previous holdings.        

The biggest development to come from the DOJ’s policy change is the requirement for a search warrant pursuant to Rule 41 of the Federal Rules of Criminal Procedure (or the applicable state equivalent) supported by probable cause in order to use the information gathered from the cell-site devices.  In addition to the search warrant, prosecutors will also have to comply with 18 U.S.C.  § 3123, which list all of the information to be included in a pen register order.  This will add a serious layer of protection for citizens, which the Supreme Court seemed reluctant to do based on their previous holdings.

There are, however, two circumstances in which a search warrant will not be required: (1) an exigent circumstance under the Fourth Amendment; and (2) an exceptional circumstance where the law does not require a warrant.  In tradition with Fourth Amendment jurisprudence, an exigent circumstance exception is not surprising, given the Supreme Court focus on reasonableness surrounding the Fourth Amendment warrant requirement.  The DOJ policy change list the garden variety circumstances where an exigent circumstance arises in the case of cell-site simulators: the need to protect human life or avert serious injury, the prevention of imminent destruction of evidence; the hot pursuit of a fleeing felon; or the prevention of escape of a suspect or convicted fugitive from justice.

The “exceptional circumstances where the law does not require a warrant” exception to the new cell-site simulator policy is somewhat confusing and vague.  The language explaining the exception states that the exceptional circumstance exception can be used when there is not an exigency, and no warrant requirement applies.  If this exception is to be used, an agent must obtain approval from executive-level personnel, the relevant U.S.  Attorney, and a Criminal Division Deputy Assistant Attorney General.  The use of the cell-site simulator must also comply with the Pen Register Statute, and the DOJ Criminal Division must track the number of times this exception is used, and the facts underlying such use.  Although the procedural safeguards will help to provide documentation of the use, the lack of examples in which this exception can be used is troubling.  Democratic Senator Patrick Leahy and Republican Senator Chuck Grassley both expressed their concerns about this broad exception in letters to the Department of Justice after hearings on Capitol Hill.

Following the warrant requirement, the new DOJ policy also requires law enforcement officers to submit to a court additional information in getting approval to use the cell-site simulators.  Law enforcement officers must describe in general the technique to be employed in using the cell-site simulator; inform the court that the target cell phone, along with other phones, might experience service interruptions; and should inform the court about how law enforcement intends to address deletion of data not associated with the target phone.

[W]hat are the remedies to someone who has their information unconstitutionally obtained by a cell-site simulator used against them, and how far and in what circumstances does the new policy apply?                                                        

Although the new improvements in the DOJ’s handling and use of cell-site monitoring devices is a step in the right direction to safeguard the data and privacy of American citizens, two major concerns are still lingering; what are the remedies to someone who has their information unconstitutionally obtained by a cell-site simulator used against them, and how far and in what circumstances does the new policy apply?

Under traditional Fourth Amendment violations, Mapp v.  Ohio and Mapp’s exclusionary rule directs courts to exclude evidence that was unconstitutionally obtained, providing an exception to the exclusionary rule does not apply.  However, these rules do not apply to evidence obtained by a cell-site simulator, according to Attorney Nate Cardozo.  Cardozo notes that this policy change is just that, a policy change.  It has not been codified into law by Congress or a federal court.  Until this happens, this policy does not have the force of law, and will most likely not keep information obtained in its violation out of court on a motion to suppress by a criminal defendant.  The lack of enforcement language in the DOJ’s policy could lead to future Supreme Court cases deciding whether the exclusionary rule applies in cell-site simulator cases.

More confusing than the lack of language in the DOJ’s policy about remedies to criminal defendants is the first footnote of the policy.  The footnote states, “This policy applies to the use of cell-site technology inside the United States in furtherance of criminal investigations.  When acting pursuant to the Foreign Intelligence Surveillance Act, Department of Justice components will make a probable-cause based showing and appropriate disclosures to the court in a manner that is consistent with the guidance set forth in this policy.”

Unfortunately, there is no solid definition of what constitutes a “criminal investigation,” as it is a term of art used by the DOJ.  So, if the DOJ is not using cell-site simulators in furtherance of whatever a “criminal investigation” is, these rules do not apply.  For example, a law enforcement agent using a cell-site simulator for “national security” purposes does not have to follow the new rules.  This provision of the law might also become a spur of litigation moving forward.

Overall, privacy activist should be happy with the new DOJ cell-site simulator policy changes.  The policy brings to the light many questions about how federal law enforcement officers use cell-site simulator devices, and seems to provide assurance that they will not be used unless a search warrant is issued on probable cause.  However, the policy is lacking in specifics, and remains a policy.  Until the policy is codified into federal and state statutes, make sure your phone is not in 2G.

Alex Rector, Staff Writer
About Alex Rector, Staff Writer (6 Articles)
Alex Rector is 2016 graduate and served as a Staff Writer for the Campbell Law Observer for the 2015-2016 academic year. He went to Campbell University and majored in Economics with a concentration in Pre-Law. Alex is originally from Hickory, North Carolina, and between undergrad and law school he worked at the Civitas Institute and the North Carolina General Assembly as the Clerk for the House Finance Committee.
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