Advances in forensic science research raises new issues everyday. Just when you thought there were was no more uncharted territory to explore, the ABA Journal brings another forensic tool into the national spotlight – a prosecutor’s use of mobile phone tracking as evidence to convict a defendant. The article, “Prosecutors’ use of mobile phone tracking is ‘junk science,’ critics say,” examines the use of mobile phone tracking and raised questions about its reliability.
The article first looks at the 2012 case of Antonio Evans. Prosecutors argued that cell phone records showed Evans could have made calls from his aunt’s house where the victim was supposedly taken after being kidnapped. Evans’ attorneys argued that the technique was not shown to be scientific. Normally, the scientific evidence goes unchallenged or is almost always let in by the court.
However, in this case, U.S. District Court Judge Joan Lefkow then wrote an opinion and order ruling that the proposed cell phone tracking evidence was unreliable. The article quotes Lefkow’s opinion that “multiple factors can affect the signal strength of a tower” and an FBI special agent’s “chosen methodology has received no scrutiny outside the law enforcement community.”
Lefkow’s ruling supports critics of cell phone tracking. The article quotes one particularly vocal critic and advocate:
“Michael Cherry, the CEO of Cherry Biometrics, a Falls Church, Va.-based consulting firm that has led the legal assault on cell tower tracking, calls it “junk science” that should never be admitted in any court for any reason. In fact, he can’t believe that such an easily disproved technique, which has been around for a decade or more, is still routinely being used in court.
“No one who understands the relevant science would ever claim that data from a single cell tower can reliably be used to specify the location of a caller at the time a particular call is made,” he says.”
But others believe that the science has some validity but is being used incorrectly. “Edward J. Imwinkelried, a law professor at the University of California at Davis who co-authored a treatise on scientific evidence, says cell tower records are not completely worthless. But they’re nowhere near as probative as many police and prosecutors would like to think.”
The problem with cell phone records is that they can tell you the area from which a call was made but cannot pinpoint the location. This is because not all phones are equipped with GPS technology, which can pinpoint a location to 50 meters.
In Evans’ case, the FBI specialist testified that his interpretation of the cell phone records could narrow Evans’ location to an area the size of a few city blocks, which included the aunt’s house. But Lefkow “refused to allow Raschke to testify that calls made from Evans’ phone could have come from the basement of his aunt’s home because he hadn’t demonstrated to her satisfaction that cell tower tracking is scientific.
The judge said that Raschke’s testimony was based on the erroneous assumption that a cellphone will always connect to the tower with the strongest signal-usually the one closest to the phone when the call is made. Yet there are a variety of factors that determine which tower a phone will connect to, including weather, topography, physical obstructions, tower maintenance and whether the phone is being used indoors or out.
Lefkow also said that Raschke had offered no proof that the tracking technique works, other than his assurances that he and other FBI agents have successfully used it to find people both living and dead, and had done so with a “0 percent” rate of error.”
So, where does this leave cell phone tracking evidence? In the same situation we’ve seen with shaken baby syndrome, arson, comprehensive lead bullet analysis and other forensic sciences. The use of science evidence needs to stop being used without the research to back up them up. Without a background in cell phone tracking, most jurists and jurors will assume that the evidence is scientifically reliable. For many, there is no reason to think otherwise. But this type of thinking does not serve justice and only increases the risk of a wrongful conviction. Let’s start the research and stop the assumptions.