In late 2009, the FBI formed a special unit dedicated to assisting in their investigations of crime utilizing the tracking and analysis of cellphone use. This agency, the Cellular Analysis and Survey Team (C.A.S.T.) has had many successes with their methods. The agency has trained over 5,000 state and local police investigators, and now they want to expand from their current 32 full-time agents. Unfortunately, besides criticisms of invasion of privacy, their methodology, especially when it comes to the area of cellphone tracking and location, has been proven flawed in many cases. One of the biggest cases to shine a light on these flaws deals with Lisa Marie Roberts, of Portland, Oregon, who was recently released from prison after serving almost twelve years for a murder she didn’t commit.
A Case of Flawed Cellphone Tracking
In 2004, Lisa Marie Roberts was told by her court appointed attorney that she should plead guilty for the 2002 murder of her girlfriend, Jerri Williams. Her attorney told her that state cellphone tracking evidence placed her phone within 3.4 miles of the park where Williams’ body was found. Her attorney told her there was no chance of acquittal.
According to a report from the Washington Post, Roberts was quoted as saying, “I just bawled. I didn’t do it.” However, she took the plea deal for a 15 year sentence. In April of this year, the guilty plea was thrown out by U.S. District Court Judge Malcolm F. Marshall. In addition to calling into question the validity of the cellphone tracking evidence [more information in the next section], witness testimony placed her more than 8 miles away from the scene of the crime, and new DNA evidence placed another suspect at the park. Roberts was released from prison at the end of May.
Cellphone Tracking: Misunderstood and Overused Science
Even though cellphone tracking has been used for years by prosecutors, experts are starting to come forward to say that the way the information is being used is flawed. While some are simply calling the technology interpretation “misunderstood,” some are even going so far as to call it “junk science.”
The idea behind cellphone tracking according to C.A.S.T. and prosecutors is that cellphone tower records can pinpoint a person’s precise location. The flawed logic is the assumption that when you make a call, it is automatically routed to the nearest cell tower. Ergo, if a crime has been committed, a search of those records can tell investigators if the suspect was in the vicinity of the crime. Here is a quick layman’s explanation of how cellphones actually work and how this information is being used in a flawed manner:
- Step 1: Hit “send” on the phone. Depending on whether it is a rural or urban area, the phone sends out a radio-frequency signal to towers within a radius of up to twenty miles.
- Step 2: A switching center evaluates the call, determines the destination and a software program “decides” which tower to connect your call based on a variety of factors.
It is this second step which causes discrepancies and invalidates the use of cellphone tracking as an investigative tool, according to experts. For example, the decision of which tower your call will use may not be the same even if you make repeated calls to the same destination in a short period of time. Sometimes a call will shift towers during the same call. This was another piece of exonerating evidence for Roberts. Apparently she had received another call moments before the one which placed her near the park. This first call came from a tower 1.3 miles away from the second call, but there was no way she could have traveled that distance in the 40 seconds that elapsed between calls.
In addition, sometimes the nearest tower may be overloaded (in the case of too many people using the tower, for example at a sporting event) or under routine maintenance, in which case your call is routed to a different tower. According to a report from The New Yorker, the only certainty is that your call will connect with a tower “somewhere within a range of roughly twenty miles.” Even if one figures half of that radius [10 miles] and the fact that most towers have three directional antennae, each covering a third of the circle, you still get an area of almost 105 square miles. Not very accurate science.
Cellphone Tracking Hits and Misses
While it’s true that this method isn’t to be trusted without question, there have been instances where investigators have been–and could potentially continue to be–successful. For example, most smartphones have G.P.S. which pinpoints your location to between 50 and 100 feet. Also, if you are under investigation, law enforcement agencies can “ping” your phone and give real-time locations.
A successful case in 2010 gave fuel to the fire driving the establishment C.A.S.T. In this case, Kelvin L. Jones, a rogue New York City police officer, staged a $1 million perfume heist. Jones was using a prepaid phone–a similar plan used by other criminals to try to mask their movements–but FBI agents were still able to create a map of locations following Jones’ movements as he pulled off the crime. This led to a successful conviction.
According to the chief of forensics for the Los Angeles County public defender’s office, Jennifer Friedman, “In every major case in Los Angeles, they use cell-tower information…It’s like fingerprints, it’s that common.” However, in a 2012 California murder case, a radio frequency engineer for AT&T testified that towers in the L.A. area have ranges of zero to 20 miles. Other experts have also added that towers can be affected by such things as topography and atmospheric conditions, and even though the FBI has claimed they run “drive tests” to confirm their data, these changing conditions make it nearly impossible to say with certainty that one day’s data matches a day being investigated in the past.
Courts are starting to agree. While there have been successes with cellphone tracking investigations, there have been numerous misses, besides the case of Lisa Marie Roberts. Enough so that many judges are no longer allowing the evidence or instructing jury members to weigh the evidence critically. Even where judges allowing the evidence, many juries, increasingly familiar with modern technology, are starting to figure it out on their own.
While the U.S. Supreme Court recently ruled that warrants must be obtained to search cellphones (which would apply to obtaining the G.P.S. chips from phones), there is currently no national protocol as to whether a warrant is required for getting call records and cellphone tower data.
[For more information on the Supreme Court decision regarding warrants to search cellphones, click on our post, Cellphone Privacy and Fourth Amendment Upheld by Supreme Court.]
In the case of Lisa Marie Roberts, to get back to the beginning, this case illustrates the importance of an experienced criminal defense attorney. Roberts’ court appointed attorney encouraged her to take the plea deal without even looking at the evidence or considering the implications or flaws. If you have been charged with a crime where the evidence deals with your cellphone, make sure you contact a criminal defense attorney who will do everything in their power to assure your rights.