Background
Jule Hannah was charged with the first-degree murder of Miguel Lopez, who was shot and killed on January 15, 2017, in Bridgeton, New Jersey. The State’s theory was that Hannah, after a car accident in Monroe Township around 7:30 a.m., was picked up by Lopez and remained in Lopez’s vehicle until it crashed in Bridgeton approximately one hour later, where Lopez was found shot four times. The State’s evidence included cell phone records showing which cell towers Hannah’s phone connected to that morning, DNA from a cigar butt found in Lopez’s car matching Hannah’s profile, and witness testimony.
At trial, the court limited Detective Sergeant Kenneth Leyman’s testimony to stating which cell towers connected to Hannah’s phone and the timing of those connections, explicitly prohibiting testimony about the phone’s specific location or antenna direction. Despite these restrictions, Detective Leyman testified that the cell site location information (CSLI) “could indicate where a suspect was” and associated the cell tower connections to the victim’s travel path. The State later told the jury that a cell phone must be “a stone’s throw” away from the tower it connects to. The jury convicted Hannah of first-degree murder and unlawful possession of a weapon.
The Appellate Division reversed, finding the trial court erred by allowing Detective Leyman to testify about historical CSLI without expert qualification. The court concluded this error carried significant weight in a largely circumstantial case and that the trial court’s limiting instructions were insufficient to cure the prejudice.
The Court’s Holding
The New Jersey Supreme Court unanimously affirmed the reversal, holding that cell site location information involves technical and specialized knowledge that must be presented by an expert witness at trial pursuant to N.J.R.E. 702. The court examined how cellular networks operate, explaining that a phone’s connection to a particular tower depends on multiple technical factors: signal strength, tower characteristics (including height and power), antenna angle and number, geography and topography, phone features, and environmental factors. The proximity of a phone to a tower is not determinable from records alone.
The court rejected the approach used in many jurisdictions that allow lay witnesses to testify about cell tower locations without expert qualification. The court noted that while a jury might technically be able to locate cell towers on a map using call records, jurors cannot draw meaningful inferences from CSLI without understanding how towers actually operate and why those locations matter. The trial court’s repeated limiting instructions throughout the trial actually demonstrated the complexity of CSLI and the necessity for expert testimony—if jurors needed detailed instructions to avoid misunderstanding the evidence, they required expert guidance to use it properly.
The court further held that the State cannot circumvent expert witness standards by presenting as a lay witness the same conclusory information that would constitute an inadmissible “net opinion” under N.J.R.E. 703 if offered by an expert. Here, Detective Leyman’s testimony that CSLI “could indicate” Hannah’s location lacked the factual support and objective data required even for expert testimony under the court’s prior decision in State v. Burney (255 N.J. 1 (2023)).
Key Takeaways
- CSLI evidence requires expert witness testimony in New Jersey; lay witness testimony about cell tower connections to establish location is inadmissible.
- A phone’s connection to a cell tower is influenced by technical factors beyond lay understanding: signal strength, tower characteristics, geography, antenna design, and environmental conditions.
- The need for limiting instructions on CSLI is itself evidence that the testimony is beyond common knowledge and requires expert guidance.
- Prosecutors cannot bypass expert witness requirements by framing technical testimony as interpretation of business records or lay witness testimony.
Why It Matters
This decision establishes a clear rule protecting defendants in New Jersey: CSLI evidence must be presented by a qualified expert who can explain the technical capabilities and limitations of cell tower data. The holding prevents lay witnesses—including law enforcement officers without telecommunications expertise—from testifying about what cell phone location evidence means, which had created risk of jury confusion and unfounded inferences of guilt.
The decision is particularly significant because it recognizes that circumstantial evidence cases built substantially on CSLI can be prejudiced by uninformed lay testimony about technical evidence. By requiring expert qualification, courts ensure juries hear evidence in proper context and understand both what CSLI can and cannot establish about a phone’s location. The ruling also prevents prosecutors from circumventing expert witness standards, which require adequate factual foundation and prohibit bare conclusory opinions, by simply relabeling expert testimony as lay witness testimony.