November 28, 2017
Discussion: SCOTUS, Carpenter & Call Detail Records
On November 29, 2017, the Supreme Court of the United States (SCOTUS) will hear arguments in the case of Carpenter v. US. At the heart of the arguments is whether or not the government (i.e., law enforcement) need a search warrant to obtain records from cellular providers for suspects in criminal incidents to help determine the location of those criminal suspects at or around the time of an incident. Previously, as detailed in the USA Today article here, SCOTUS and lower courts have upheld that a search warrant is not required because the records are not subject to Fourth Amendment privacy restrictions due to the fact that the data (i.e., the records) are transmitted to a third party, being the cellular provider. This is what is known as the “Third Party Doctrine”. It has been cited in previous cases where a third party, such as a utility company, holds records that may be relevant in a criminal investigation and the burden of documentation on the government has heretofore been a subpoena for records, not a search warrant. Because a search warrant requires probable cause to be stated, the standard would be higher to obtain the records.
Think of it this way: Subpoena = “I want this”
Search Warrant = “I want this, and here is why”
Call Detail Records… Sort of
Setting the Records Straight
I’ve read a lot online about this case. A recent posting on PoliceOne.com erroneously leads the reader to believe that this case is about data contained on the cell phone, much like the often-argued Apple vs. FBI cases that keep popping up in the wake of active shooter/terrorist incidents (Read this blog’s take on that here: https://prodigital4n6.com/clash-of-the-titans-apple-vs-the-u-s-government/ ). Let me be clear: This case is not about cell phone data, forcing people to hand over their pass codes or allowing the government to pry into your device! This case is about cellular location data subscribers virtually never see. It is about records of cell site location data stored with your cellular provider, along with sending and receiving phone numbers for calls and texts, duration of calls and potentially locations of cell sites used for data transmissions when you check Facebook or your email. You never see most of this data and if you call your cellular provider, they won’t give it to you without a subpoena.
To Get A Warrant Or Not? That is the Question!
Some brief background is in order before opining on this subject…
I’m a former law enforcement investigator with 15 years total experience. I worked as the sole investigative member for my agency on the Internet Crimes Against Children Task Force for several years and have investigated hundreds of electronically-facilitated crimes, which meant that I had to author dozens of search warrants and subpoenas. In Virginia, there is a law that allows police to obtain subscriber information only for users of internet service providers in child exploitation cases. These “administrative subpoenas” need to be signed by a prosecutor and can simply be faxed to the provider to obtain name, address, phone number, email address and any other registrant information for the user of a screen name, email address, IP address, etc. It is to be used in child exploitation cases only and no additional records are available through this process.
Each and every prosecuting attorney I’ve ever been trained by or worked with (and I’ve worked with some of the best at electronic crime prosecution) has a rule: When in doubt, get a search warrant. In fact, for cellular call detail records (CDRs), there is often a need to bypass a subpoena and get a search warrant, especially when requesting more than simple records – things like text message content. You see, the law distinguishes between things like simple records and unique content of text messages, so the burden of the request is naturally higher when the police ask for content of email, text messages, etc. vs. simple records of who logged onto the service, when and from where. It’s an important distinction and one that SCOTUS will no doubt delve into in great detail during arguments in this case.
These things are everywhere!
Since leaving law enforcement and for nearly the past 4 years, I’ve been working mainly civil cases in the digital forensic field in a litigation support arena. I’ve also been working cases involving analysis and mapping of cellular call detail records, so I’ve been involved in assisting attorneys on verbiage for the requests of these records, obtaining the records, analyzing the records and using them to prove or disprove location, link analysis and other items of interest in litigation. A few of these cases have been retained by criminal defendants, so I have the benefit of experience at the prosecution end and the defense end to add credence to the next bit of information…
It’s very simple: In most cases, getting a search warrant helps the prosecution and helps bolster the credibility of the evidence. In most cases where a search warrant isn’t obtained and that fact is argued by the defense, the arguments help to bolster the defense and sometimes leads the evidence, such as cellular call detail records, to be thrown out.
That being the case, my question to government investigators everywhere is, why not just get a search warrant anyway?
Yes, there are exceptions to every “search warrant rule”, exigency being the most obvious. But absent exigency, a search warrant should probably be sought.
Investigative Lead vs. Evidence
Part of what’s the heart of this argument is whether or not CDRs constitute an investigative lead or evidence. When police request a “tower dump” of all devices connected to a particular cell site in a given time frame around a crime to help generate a potential suspect list or prove/disprove a suspect was in the area at the time of the crime, that serves as an investigative lead, but it can also quickly turn into evidence. I would submit that investigative leads alone do not require a search warrant. By their very nature, they are lacking in specific evidence in support of them, so a search warrant likely isn’t feasible. However, I would further submit that a “tower dump” and the data derived therefrom also doesn’t fall under the category of a specific subscriber’s (i.e., target’s) call detail records. They are records maintained by the cellular provider, but not specific to any one subscriber.
Only after a suspect list has been developed and substantial information gathered to develop actionable intelligence can we start to cross the bridge into evidence. It also cannot be overlooked that sometimes, cellular location evidence serves to exonerate a suspect, by proving he (or his device) was not in the area at the time of the incident. Either way, the importance of evidentiary data in, contrast to investigative leads, dictates that obtaining a search warrant is likely the prudent move.
Wrapping it Up
Back when the Third Party Doctrine was originally held, wireless cell phones were just an idea. In 2017, we use them to stay connected in our everyday lives. They help us keep in contact with friends and loved-ones, facilitate banking transactions, arrange transportation and much more. The devices themselves store a very large amount of data, but they cannot do it without internet connectivity, which is what the cellular providers do for us. The weight of cellular location evidence in both criminal and civil cases has grown exponentially in the modern era and will only keep growing as time goes on and cellular networks transition from 4G to 5G technology.
My prediction: SCOTUS will hold that the government needs a search warrant to obtain cellular records of a specific subscriber or target of an investigation. However, they need to understand and explicitly distinguish between records for a specific subscriber needing a search warrant vs. tools police use to generate investigative leads, for which the burden of the request should be much lower. Such is the case when requesting tower dumps. Only by making that distinction clear will they serve to help answer additional questions in subsequent cases and put the matter entirely to rest… until next time!
Patrick J. Siewert
Professional Digital Forensic Consulting, LLC
Virginia DCJS #11-14869
Based in Richmond, Virginia
Available Wherever You Need Us!
We Find the Truth for a Living!
Computer Forensics — Mobile Forensics — Specialized Investigation
About the Author:
Patrick Siewert is the Principal Consultant of Pro Digital Forensic Consulting, based in Richmond, Virginia. In 15 years of law enforcement, he investigated hundreds of high-tech crimes, incorporating digital forensics into the investigations, and was responsible for investigating some of the highest jury and plea bargain child exploitation investigations in Virginia court history. Patrick is a graduate of SCERS, BCERT, the Reid School of Interview & Interrogation and multiple online investigation schools (among others). He continues to hone his digital forensic expertise in the private sector while growing his consulting & investigation business marketed toward litigators, professional investigators and corporations, while keeping in touch with the public safety community as a Law Enforcement Instructor.