Historical cell site location information (CSLI) has been offered as objective, scientific location evidence in criminal trials, but is far less precise than the claims it is used to support. Not only is there no way to pinpoint a cellphone’s precise geographic location from historical CSLI, but there are also no known validation or error rates for the methodologies used to collect and analyze this data. A 2019 telecommunications scandal in Denmark revealed gross inadequacies in the cellphone data and software used by law enforcement to analyze this type of evidence. The scandal sent shockwaves through the country’s legal community and led to a temporary moratorium on the use of cellphone location evidence, a comprehensive investigation into data collection and analysis practices, and the adoption of extensive reform and improvement measures. Perhaps even more importantly, the scandal undercut the trust and acceptance previously afforded to this type of evidence. Taking from the lessons learned in Denmark, this Note attempts to lay out what is known and unknown about historical CSLI and how the current state of this type of evidence comports with the Federal Rules of Evidence. In Part I, this Note first examines how and why historical CSLI is produced. Part II summarizes the current known issues with this type of cellphone location evidence. Finally, Part III sets forth the evidentiary shortcomings of historical CSLI that may be raised in criminal trials.
Victoria Saxe, Junk Evidence: A Call to Scrutinize Historical Cell Site Location Evidence, 19 U.N.H. L. Rev. 133 (2020).