True crime TV shows and movies have captivated audiences for years. In late 2014, however, it was the podcast Serial, a week-by-week retelling of a true crime mystery in Baltimore that captivated audiences across the globe and thrust expert witnesses into the spotlight. For those who are not amongst the 40 million global listeners who tuned in to this addictive weekly podcast, Serial delves into the 1999 murder of 18-year-old Baltimore student Hae Min Lee. The cause of death was identified as manual strangulation. Despite the lack of eye-witnesses or physical evidence tying anyone to her murder, her ex-boyfriend and classmate, Adnan Syed was charged with her murder.
He was later convicted as a result of controversial “cell phone evidence” and the testimony of an acquaintance, Jay Wilds, who alleged that he assisted Syed in burying Lee’s body. Syed, 17 at the time of the murder, received a life sentence which he continues to serve in a Maryland prison.
Expert Evidence in the Trial of Adnan Syed
Due to the lack of DNA or eye witness evidence linking Syed to the crime, the State relied on the records of Syed’s mobile phone to attempt to corroborate the timeline of events provided by Wilds. Without the cell phone evidence, the case came down to a “he said, she said” — or in this case, “he said, he said”— situation between Wilds’ version of events and Syed’s unwavering denial of involvement in Lee’s murder.
The State used the cell phone records which were corroborated by an expert at trial as a locator for where the phone, and by virtue Syed, was at various times on the night of the murder. Whenever a phone call was made or received, a mobile phone tower would be “pinged”. By looking at the area of land that the “pinged” phone tower covered, the State alleged that this was where Syed was located at a particular time. The most incriminating “ping” was a call placing the phone in the park where Lee’s body was later recovered at the time that Wilds’ alleged that he and Syed were burying Lee’s body.
In Syed’s case, a cell phone expert was called by the prosecution to give evidence at trial in relation to the cell phone evidence. The method used by the expert to determine which tower was “pinged” at a certain location was simply to drive to a certain location connected to Wilds’ timeline of events, make a call and note which tower the call “pinged”. In this case, the prosecution obtained information about 14 different locations connected to the trial. Only four of these were raised at trial by the expert, since the other 10 tests did not support their contended version of events.
While it cannot be pinpointed exactly what evidence led the jury to finding Syed guilty of the murder, the cell phone evidence, which provided the only corroboration for Wilds’ timeline of events, undoubtedly played a role. But just how reliable was this evidence?
Scepticism of Cell Phone Evidence Use in US Trials
Interestingly, Syed’s trial was the first in the state of Maryland to use cell phone evidence of this kind. In succeeding cases, doubt was cast over the reliability of such evidence, with Federal Courts in Oregon and Illinois ruling cell phone evidence inadmissible partly due to the overstatement of its accuracy. The Washington Post also investigated the use of cell phone evidence, noting its key failure as the assumption that cell phones always use the closest cell tower (i.e “ping” the tower closest to their physical location). However, numerous experts continue to insist that this method is incorrect.
This is because cell phones do not always necessarily “ping” the closest tower but rather are routed to a tower that best services the phone network based on numerous factors. In addition, the range of certain towers often overlaps with other towers, and the size and shape of a tower’s range is also constantly changing.
In a 2012 murder trial in California, a radio frequency engineer gave expert testimony on the use of cell phone evidence stating that “it is not possible for anyone to reliably determine the particular coverage area of a cell-tower antenna after the fact based solely on historical cell-tower location or call- Experts say law enforcement’s use of cell phone records can be inaccurate (June 27 2014) detail records”. He noted that weather, time of day, types of equipment, technology, and call traffic also impact on the cell records that are produced.
Lisa Marie Roberts was wrongfully convicted in Portland, Oregon using cell phone records, in a chillingly similar manner to Syed. At the time of the murder for which she was convicted, her cell phone records “pinged” a location which covered the site where the body of her then partner was later recovered. The expert giving evidence in her defence noted as follows:
“There are so many different factors [involved] that two cellular devices stationed next to each other making phone calls at the same moment could still get different towers… I’ve seen proof that two individuals, subscribed to the same cellular provider, standing next to each other — on surveillance — can still get different towers.”
Roberts pleaded guilty on the advice of her legal counsel as a result of the seemingly incriminating cell phone evidence and served 12 years’ imprisonment. In 2014 her guilty plea was thrown out after it was established that the tower her cell phone “pinged” had a range of more than 300 square miles.
It is beyond question that serious doubt has been cast over the reliability of the use of cell phone evidence since the trial of Adnan Syed 16 years ago. One team of Maryland lawyers have delved further into the Syed trial, unearthing new evidence on the reliability of the precise cell phone data used in the trial and in relation to medical expert witness which could have been raised to refute the cell phone evidence. In part 2 of this blog we explore exactly what has been uncovered and what this means for Syed.