United States v. Medley
312 F. Supp. 3d 493
D. Maryland2018Background
- Defendant Jovon Lovelle Medley is charged with carjacking resulting in serious bodily injury, a § 924(c) firearms count, and being a felon in possession of a firearm. Identification by victim was impossible because the assailant wore a mask.
- The Government designated FBI SA Richard Fennern as an expert to analyze historical cell site location records from Medley’s Sprint phone and to map cell towers/sectors near the crime time.
- Fennern used call detail records, cell site location records, and Per Call Measurement Data, then mapped tower locations and sectors to opine the phone was in the general area of the crime shortly before the offense.
- Medley moved in limine to limit Fennern’s testimony, arguing the charts and sector-shaded maps invite impermissible precision and overstate what the data support. He did not challenge Fennern’s qualifications or the factual basis of the records.
- The Government sought to present Fennern’s opinion that the phone’s location was “consistent with” the crime scene; the court allowed such testimony only after mandatory, clear explanation of methodological limits and that the phone can only be placed within a broad cell-sector, not at a precise point.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Admissibility under Rule 702 of expert testimony about historical cell-site analysis | Government: SA Fennern is qualified; methodology reliable to show general location; limitations will be disclosed | Medley: The analysis and maps overstate precision and may mislead jury; seek limits on charts/claims | Court: Testimony admissible as expert under Rule 702 but subject to Daubert-style limits and required disclosure of accuracy/limitations |
| Whether cell-site testimony should be lay or expert | Government originally could elicit technical testimony; chose to designate Fennern as expert | Medley: technical mapping is expert territory and must meet Rule 702 | Court: Technical explanation of how towers and sectors operate is expert testimony and must comply with Rule 702 |
| Scope of opinion about defendant’s location from historical records | Government: may say phone was "consistent with" location of crime scene in general area | Medley: prevents overprecision; charts could imply phone was at scene | Court: Government may elicit that the phone was in the general cell-sector and that location was "consistent with" the scene only after the expert fully explains limitations; expert may not place phone at exact location |
| Use of demonstrative maps/sector shading | Government: maps helpful to explain tower locations and sectors | Medley: shaded areas invite impermissible inference of precise location | Court: Maps admissible but expert must first explain imprecision; defense may cross-examine and use learned treatises under FRE 803(18) |
Key Cases Cited
- United States v. Hill, 818 F.3d 289 (7th Cir. 2016) (historical cell-site analysis can reliably show general area but may overpromise precision)
- United States v. Graham, 796 F.3d 332 (4th Cir. 2015) (discusses lay vs expert lines for cell-site testimony)
- United States v. Graham (en banc), 824 F.3d 421 (4th Cir. 2016) (addresses scope of technical testimony by records custodians)
- United States v. Natal, 849 F.3d 530 (2d Cir. 2017) (testimony on how towers operate constitutes expert testimony)
- United States v. Jones, 918 F. Supp. 2d 1 (D.D.C. 2013) (FBI agent admitted as expert to map cell towers and explain location analysis)
- United States v. Reynolds, [citation="626 F. App'x 610"] (6th Cir. 2015) (criticizes cell-site methodology and urges scientific community standards)
- Daubert v. Merrell Dow Pharm., 509 U.S. 579 (1993) (trial judge as gatekeeper for expert reliability)
- Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999) (Daubert principles apply to technical experts)
- Gen. Elec. Co. v. Joiner, 522 U.S. 136 (1997) (abuse of discretion standard for admitting expert testimony)