United States District Court, E.D. Michigan, Southern Division
ORDER DENYING DEFENDANT'S MOTION FOR A DAUBERT
HEARING AND TO PRECLUDE TESTIMONY OF GOVERNMENT'S
PROPOSED EXPERT CELLULAR ANALYSIS [DOC. 774]
CARAM STEEH UNITED STATES DISTRICT JUDGE
matter is before the court on defendant Corey Bailey's
motion for a Daubert hearing and to preclude
testimony of government's proposed expert cellular
analysis. The motion is joined in by defendants Arlandis Shy
[doc. 797], Billy Arnold [doc. 780] and James Robinson [doc.
804]. The motion has been briefed and a response was filed by
the government. The court also had the opportunity to hear
the testimony of the government's cellular analysis
expert, FBI Special Agent Joseph Jensen, who was permitted to
testify during the first trial held in this case. The court
does not believe oral argument would further aid its
determination of this matter.
government disclosed that it will seek to introduce expert
testimony of Agent Jensen regarding an analysis of cellular
telephone business records from various telephone numbers
associated with certain defendants (Arnold, Bailey, Porter,
Brown, Robinson). Agent Jensen authored a report entitled
“FBI Cellular Analysis Survey Team” including
seven target cell phone numbers and their activity at certain
times on July 14, 2014, May 1, 2015, May 8, 2015, May 10,
2015, May 24, 2015 and June 7, 2015. These dates and times
correspond with some of the murders/shootings which form the
basis for the charges in this case.
will testify that he has received training both by the FBI
and the major cellular providers as to how to interpret and
map the location information provided by the phone companies
as part of their business records. He will testify that
during a call, a cellular phone connects to the cell tower
with the strongest and clearest signal, and that it is
possible to learn the general location of a cell phone as it
is used to make and receive calls. Jensen will explain that
he was given dates and times of various incidents in this
case and that he compared that information with the cell
phone records. Jensen will testify that based on his
analysis, he was able to determine that the cell phones in
question utilized cell towers in proximity to the various
crime scenes. Jensen will show the jury maps depicting a
particular phone making or receiving a communication at a
specific time and utilizing a particular cell tower and
sector, as represented by pie-shaped symbols on the maps. The
pie-shapes represent the direction the antennas on the cell
towers were oriented at the time of the communication. The
shaded areas show the primary direction the radio frequencies
(RF) travel from antennas - they indicate the general area
where the cell phone was located at the time of the
communication and do not depict the actual RF coverage area
of the particular sector. Jensen will explain that he cannot
testify about a defendant or cell phone's precise
location using this method of analysis.
argue that the proposed expert opinion testimony does not
meet the requirements of FRE 702 and 403. Federal Rule of
Evidence 702 provides that a witness who is qualified as an
expert may testify in the form of an opinion when:
(1) the expert's scientific, technical, or other
specialized knowledge will help the trier of fact to
understand the evidence or to determine a fact in issue; (2)
the testimony is based on sufficient facts or data; (3) the
testimony is the product of reliable principles and methods;
and (4) the expert has reliably applied the principles and
methods to the facts of the case.
FRE 702. To assess the reliability of an expert's
methodology, the Supreme Court has set out four factors to
consider: (1) whether the theory is based on scientific or
other specialized knowledge that has been or can be tested;
(2) whether the theory has been subjected to peer review; (3)
the known or potential rate of error and the existence of
standards controlling the theory's operation; and (4) the
extent to which the theory is generally accepted in the
relevant community. Daubert v. Merrell Dow
Pharmaceuticals, 509 U.S. 579, 593-94 (1993).
Sixth Circuit has held that a district court is not required
to hold a hearing to comply with Daubert so long as
it "keeps watch over the proceedings, and, with the aid
of objections from [counsel] eliminates methodologically
unsound or irrelevant expert testimony.” Avery
Dennison Corp. v. Four Pillars Enterprise Co., 45 F.
App'x 479, 484 (6th Cir. 2002). This court presided over
the first trial in this case in which Agent Jensen was
permitted to testify about the exact methodology at issue in
defendant's motion. The court is satisfied that a
Daubert hearing is not required to determine the
reliability of Agent Jensen's methodology.
Jensen possesses specialized knowledge
Agent Jensen has been an FBI agent for over seven years. In
2014 he received 40 hours of training from the FBI's
Cellular Analysis Survey Team (“CAST”) in basic
cellular telephone call detail analysis. Over the course of
the past year, Jensen received 260 hours of training in
advanced analysis of cellular record analysis, cellular
theory, RF technology and propagation, cellular network
architecture, and cellular technologies. In 2016 Jensen
completed CAST certification training. Jensen has testified
as an expert in cellular telephone call detail analysis in
this district, including in the first trial in this case.
United States v. Gomez, 15-20087 (J. Michelson);
United States v. Brownlee, 16-20319 (J. Cleland);
United States v. Woodley et al., 15-20007 (J.
Michelson); United States v. Dupree, 15-20457 (J.
Leitman); United States v. Wiggins, 16-20644 (J.
Murphy). He has also been recognized as an expert in Wayne
and Monroe County Circuit Courts.
court finds that based on his experience and training, Jensen
possesses an expertise in cellular analysis.
Cell-Site location data is widely recognized and
cell location evidence has passed Daubert analysis
in multiple federal courts. United States v.
Pembrook, 876 F.3d 812, 824-25 (6th Cir.
2017). Jensen will testify that cellular phone business
records, provided by service providers, reveal which cell
tower and sector a cell phone utilized at a given moment. He
will also testify that a typical cell tower has three
120-degree antennas (or “sectors”). Jensen will
testify that a cell phone will seek the tower with the
strongest, clearest signal when it requests and connects with
a communication channel on the network. He will testify that
the strongest, clearest signal generally comes from the tower
that is closest to the phone or the tower with the best line
will concede that the strongest, clearest signal can be
affected by a number of factors including signal strength,
weather, maintenance schedules of certain cellular towers,
topography, and man-made structures. See United States v.
Freeman, 2015 WL 2062754, at *5 (E.D. Mich. May 4, 2015)
(“[t]he fact that an expert did not take into account
various factors that may affect the signal strength of a
tower or impact its coverage range does not render the
fundamental methodology of cell site analysis unreliable.
Instead, the absence of those considerations ...