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Alabama Supreme Court Announces Testimony About Cell-Site Location Data Is ‘Scientific’ Expert Testimony, Not Lay, Triggering Daubert Analysis

by Anthony Accurso

In its January 8, 2021, opinion, the Supreme Court of Alabama held that a law enforcement agent’s testimony about how historical cell-site data could be used to determine the approximate location of the defendants’ cellphones is scientific testimony, and as such, it must be properly assessed for admissibility under the state’s rules of evidence for scientific reliability.

Marcus King George and Alyssa Sue Watson were indicted for their roles in the kidnapping and murder of Samantha Payne in the early morning hours of November 2, 2015. Payne was suspected of informing to law enforcement about illegal activities, such as sales of methamphetamines. Payne was allegedly murdered by Mike Belcher, a co-conspirator of George and Watson’s, in Talladega National Forest.

George and Watson pleaded not guilty and proceeded to trial. The State notified the defense it intended to call Allison Duncan to testify about relevant historical cell-site location data linking defendants to the murder. Duncan was an intelligence analyst with the Alabama Law Enforcement Agency, and the State sought to classify her testimony as “lay,” based on her unique experience.

The defense objected and requested a hearing to determine whether Duncan’s testimony would be considered “lay” or “scientific” and, if ruled the latter, whether it would be admissible under the state’s rules of evidence.

During the hearing, the defense offered the testimony of Manfred Schenk, an expert in radio frequency and cellular technology. Schenk testified to the complexities of the technology and engineering behind what most people experience as the simplicity of making a cellphone call. One key statement made was: “[T]here’s a correlation between signal strength and distance. But an actual distance we do not know.” Also, when asked the following: “[T]he theory for being able to project where a cellphone was being received or was being directed from, would that be some type of scientific theory?”; his answer was “surely.”

Duncan testified that she considered herself “to be an expert in call detail record analysis.” However, when the defense objected to this characterization, the State said it had “not tendered [Duncan] as an expert at this point.”

The trial court determined that, while technical, Duncan’s testimony was not scientific.

During trial, the defense objected again when the State motioned to admit a map that was based, in part, on the cellular activity of Watson. The State responded by saying, “Judge, this witness, if she were qualified as an expert – which the State would contend that she is – would be able to, according to Rule 703[, Ala. R. Evid.], rely on data information that had not been admitted into evidence to reach her conclusion.”

When Duncan was testifying, in part based on the map, the defense again objected. The State argued in response that Duncan “can use information and data in formulation of her opinion” and that she “can rely on data and information not in evidence because she is an expert.”

Duncan further testified as to her use of software known as “PenLink” to “read[] the information” from the cellphone providers’ logs to generate the map details used during the trial.

Both George and Watson were ultimately convicted at trial and sentenced each to 30 years’ imprisonment. They appealed, arguing that Duncan’s testimony should have been classified as “scientific” expert testimony and screened for reliability under Alabama Rules of Evidence Rule 702(b). The Court of Criminal Appeals affirmed their convictions, ruling that Duncan’s testimony was not scientific and in fact it was lay testimony, not expert. The defendants appealed to the Alabama Supreme Court.

In analyzing this issue of first impression, the Court reviewed the language of Rule 702(n), which provides in pertinent part that “expert testimony based on a scientific theory, principle, methodology, or procedure is admissible only if: (1) the testimony is based on sufficient facts or data; (2) the testimony is the product of reliable principles and methods; and (3) the witness has applied the principles and methods reliably to the facts of the case.”

Previously, in Mazda Motor Corp. v. Hurst, 261 So. 3d 167 (Ala. 2017), the Alabama Supreme Court discussed a framework of principles to determine whether testimony is either “lay” or “scientific.” This case largely rested on the U.S. Supreme Court’s decision in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), the seminal case setting forth the analytical framework in distinguishing expert testimony between “scientific” evidence and “technical[] or other specialized knowledge” and their admissibility into evidence.

In explaining a trial court’s responsibility to distinguish between the two types of expert opinion testimony, the Mazda Court, said, “As amended, Rule 702 requires courts to make two separate but related determinations regarding scientific evidence. First, pursuant to the first sentence in Rule 702(b), the trial court must determine whether proffered expert testimony purports to be scientific. If so, a Daubert admissibility inquiry is triggered, and the trial court then must determine whether the purportedly scientific evidence is ‘reliable’ – that is, meets the three-pronged admissibility standard imposed by Rule 702(b)(10-(3).”

Further, “a person who offers an opinion as a scientific expert must prove that he relied on scientific principles, methods, or procedures that have gained general acceptance in the field in which the expert is testifying.” Swanstrom v. Teledyne Cont’l Motors, Inc., 43 So. 3d 564 (Ala. 2009).

As for a reasonable standard for determining the difference in types of expert testimony, “in short, a scientific expert is an expert who relies on the application of scientific principles, rather than on skill – or experience-based observation, for the basis of his opinion.” Carmichael v. Samyang Tire, Inc., 131 F.3d 1433 (11th Cir. 1997).

A helpful example in illustrating the difference between the two types of opinion testimony comes from Berry v. City of Detroit, 25 F.3d 1342 (6th Cir. 1994). If one needed testimony on the flight of bees, “an aeronautical engineer ... could apply general [flight] principles to the case of the bumblebee. Conceivably, even if he had never seen a bumblebee, he would still be qualified to testify, as long as he was familiar with its component parts.” The engineer would be a scientific expert.  On the other hand, “if a proper foundation were laid for his conclusions,” a beekeeper could testify as to whether bumblebees always take off into the wind. “The foundation would not relate to his formal training but to his firsthand observations. In other words, the beekeeper does not know any more about flight principles than the jurors, but he has seen a lot more bumblebees than they have.” The beekeeper would not be a scientific expert; instead, his expertise would be based upon specialized skill or experience.

As the court in Carmichael summarized, “the question in this case is whether [the expert’s] testimony is based on his application of scientific principles or theories (which we should submit to a Daubert analysis) or on his utilization of personal experience and skill.”

In the present case, the State argued Duncan was trained in historical cell-site data analysis and that she “based her conclusions on her interactions with cell service providers and her training.”

However, the Court noted that her testimony went well beyond the call-detail records and “concern[ed] whether that data is a reliable indication of the location of the cellular device from which the call was made at the time the call was made.”

Also, “the PenLink software, for which Duncan received extensive training, purported to determine the direction from which the signals from Watson’s and George’s cellular telephones connected to a particular antenna; based on Schenk’s testimony, such a determination requires the application of scientific theory.”

Finding the issue sufficiently reliant on scientific theory, the Court held that testimony relating to historical cell-site data analysis is properly characterized as “scientific” and thus triggers a Daubert admissibility analysis. The Court explained that Duncan’s “experience and training” on the PenLink software could not obfuscate both her and the software’s underlying dependence on scientific “principles and methods.”

Additionally, the Court rejected the Court of Criminal Appeals’ conclusion that Duncan’s testimony constituted lay testimony, not expert. The Court explained that Duncan provided testimony that clearly required “specialized knowledge,” and thus she testified as an expert witness.

The Court noted that the majority of courts that have ruled upon this issue are in accord with its conclusion, with few exceptions. However, the Court also observed that a small number of courts have ruled that testimony about historical cell-site location data is admissible via a lay witness, as opposed to requiring either a scientific or non-scientific expert witness, citing United States v. Evans, 892 F. Supp. 2d 949 (N.D. Ill. 2012).

Accordingly, the Court reversed the decision of the Court of Criminal Appeals and remanded the case to the trial court “for a hearing to be held to determine whether Duncan’s scientific testimony satisfies the admissibility requirements of Rule 702(b).” See: George v. State, 2021 Ala. LEXIS 1 (2021).

Editor’s note: This opinion is an excellent starting point for anyone interested in admissibility of expert (or lay) witness opinion testimony regarding historical cell-site location data. The Court engages in a thorough analysis of the issue, citing and discussing several court opinions from other jurisdictions.

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