USA v. Tuttle et al.

UNITED STATES DISTRICT COURT
DISTRICT OF SOUTH DAKOTA
WESTERN DIVISION
UNITED STATES OF AMERICA,
Plaintiff,
vs.
FRANCISCO VILLANUEVA,
a/k/a “Gumby,” a/k/a “Pancho,”
ADAN JAMES CORONA,
a/k/a “Ace Boogie,”
Defendants.
CR. 17-50049-02 & 03-JLV
ORDER
INTRODUCTION
The government provided a notice of expert witness as to South Dakota
Division of Criminal Investigation Special Agent (“S.A.”) Brent Gromer. (Docket
488). Both defendants filed Daubert1 challenges to S.A. Gromer’s testimony.
(Docket 579 & 587). The government filed a response to defendants’
challenges. (Docket 617). Defendants’ filed a reply brief in support of their
challenge. (Docket 632). For the reasons stated below, defendants’ Daubert
challenges are denied.
1Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 592 (1993).
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ANALYSIS
LEGAL STANDARD
Rule 702 of the Federal Rules of Evidence governs testimony by expert
witnesses and states as follows:
A witness who is qualified as an expert by knowledge, skill,
experience, training, or education may testify in the form of an
opinion or otherwise if:
(a) the expert’s scientific, technical, or otherwise
specialized knowledge will help the trier of fact to
understand the evidence or to determine a fact
in issue;
(b) the testimony is based on sufficient facts or
data;
(c) the testimony is the product of reliable
principles and methods; and
(d) the expert has reliably applied the principles and
methods to the facts of the case.
Id. “Rule 702 does not rank academic training over demonstrated practical
experience.” United States v. Roach, 644 F.3d 763, 764 (8th Cir. 2011).
The trial court must ensure that expert testimony or evidence admitted is
not only relevant, but reliable. Daubert, 509 U.S. at 589.2 Faced with a proffer
of expert testimony, the court must determine at the outset whether the expert
is proposing to testify to (1) scientific, technical, or other specialized knowledge
that (2) will assist the trier of fact to understand or determine a fact in issue.
Id. at 592. “Federal Rule of Evidence 702 provides that an expert may testify if
it will assist the trier of fact to understand the evidence or determine a fact in
2Although Daubert deals specifically with expert testimony based on
scientific knowledge, the Supreme Court extended the principles in Daubert to
all expert testimony. Kumho Tire Co. Ltd. v. Carmichael, 526 U.S. 137, 141
(1999).
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issue.” United States v. Geddes, 844 F.3d 983, 991 (8th Cir. 2017) (internal
quotation marks and citation omitted). The trial court’s decision to admit
expert testimony is reviewed for an “abuse of discretion, according it
substantial deference.” United States v. Bailey, 571 F.3d 791, 803 (8th Cir.
2009).
Vigorous cross-examination, presentation of contrary evidence and
careful instruction on the government’s burden of proof are the traditional and
appropriate means of attacking shaky but admissible evidence. Daubert, 509
U.S. at 596. See also Johnson v. Mead Johnson & Co., LLC, 754 F.3d 557 (8th
Cir. 2014) (same).
GOVERNMENT’S NOTICE
The government provided a notice of expert witness as to S.A. Gromer.
(Docket 488). S.A. Gromer’s curriculum vitae (“CV”) is attached to the
government’s notice. (Docket 488-1). Since 2010, S.A. Gromer has been a
member of the South Dakota Internet Crimes Against Children (“ICAC”) Unit
and is currently the ICAC Commander. Id. at p. 1.
The notice indicates “[b]ased on his training and experience and based
upon published materials,” S.A. Gromer will testify “to the functionality and
features of Facebook.” (Docket 488 at p. 1). According to the government, the
specific areas of his testimony in this case are:
A. Agent Gromer is familiar with features of Facebook. . . . [He]
is familiar with understanding Facebook records returned by
the company pursuant to search warrants. Such records
include information that is not necessarily visible to
individual users when utilizing Facebook on their computers
or phones, such as information on URL links, IP addresses,
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time and date messages or data are sent, and user
identification data.
B. Agent Gromer will testify that in Facebook records when a
user is identified as an “author” it means that is the user
who originated the transmission.
C. Agent Gromer will testify Facebook can be used to make
audio calls between users and users can leave each other
voicemails that are retained in Facebook records. In records,
the user who made the audio call would be identified in
records as the “author.”
D. Agent Gromer will testify Facebook records can identify
whether a user deleted messages.
E. Agent Gromer will testify to commonly used Facebook
terminology.
Id. at pp. 1-2. The government’s notice represents that S.A. Gromer has
testified numerous times in South Dakota state court and federal court. Id. at
p. 2.
Defendants’ Challenges
Both defendants filed Daubert challenges to the government’s notice of
S.A. Gromer.3 (Dockets 579 & 587). Defendants contend “[w]hile it is clear
that Agent Gromer has significant experience with law enforcement,
investigations, and digital evidence collection and forensics, it is murky, at
best, as to his experience with ‘functionality and features of Facebook.’ ”
(Docket 579 at p. 2). Addressing the agent’s training, defendants argue his “CV
does not reference any training generally to Facebook, or specifically to its
3Unless otherwise indicated a citation to one of the defendant’s
submissions is intended to apply equally to the other defendant’s argument.
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features and functionality. In fact, the [agent’s] CV never references any
specific experience or training regarding Facebook at all.” (Docket 587 at p. 1).
In addition to asserting S.A. Gromer is not qualified to express “an expert
opinion on Facebook’s functionality and features,” defendants assert “the
government’s notice is vague as to what his opinions are.” Id. at p. 2. As an
example, defendants point out the notice indicates the agent “believes that
Facebook records can identify whether a user deleted messages, but no
specifics are given as to whether he believes that occurred in this case, where it
occurred, what suggests it occurred[.]” Id. Finally, defendants claim the notice
is deficient because it states the agent’s “opinions ‘will be to a reasonable
degree of certainty’ without identifying any standard by which this reasonable
degree of certainty will be compared.” Id.
“For these reasons,” defendants ask the court to “prohibit the
government from introducing or eliciting testimony from Gromer on the matters
listed in its notice. Alternatively, prior to admitting this evidence, the Court
should conduct an evidentiary hearing[.]” Id. at pp. 3-4.
Government’s Response
The government opposes defendants’ challenges. (Docket 617). The
government asserts S.A. Gromer’s testimony is “experienced-based.” Id. at
p. 2 (internal citation omitted). S.A. Gromer “is qualified to testify to numerous
topics related to electronic service providers, including Facebook” according to
the government “and has been permitted to testify regarding such electronic
service providers previously.” Id. (federal cases referenced omitted).
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The government argues the agent’s “testimony is relevant and will aid the
jury in understanding Facebook as an online communication forum, which
some jurors may not use and is foreign to them.” Id. at p. 3. By way of
example, the government submits “when Facebook designates a user as an
‘author’ of an audio file it means that user is the one who initiated the
communication.” Id. In the government’s view, authorship is important
“because Corona made an audio file recording admitting to his relevant
conduct in this case.” Id. at pp. 3-4. Because the users’ language on Facebook
may be foreign to non-users, the government submits some “translation” may
be necessary and the agent “is qualified to offer those explanations based on
his extensive experience regarding Facebook and other online
communications.” Id. at p. 4.
For these reasons, the government asks that defendants’ objections be
overruled and S.A. Gromer be permitted to testify consistent with the
government’s notice. Id. at p. 4.
Defendants’ Reply
Defendants contend “[t]he fact that [S.A. Gromer] has ‘experience’ and is
‘familiar with understanding Facebook records returned by the company
pursuant to search warrants,’ . . . does not make him an expert.” (Docket 632
at p. 1). Arguing the witness “has no specific training regarding Facebook,” the
defendants submit his experience “offers nothing to suggest that his experience
will provide the jury with opinions that can be tested, have been subject to peer
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review, contain error rates, what his methods and procedures are and whether
they have been generally accepted in the community of Facebook experts.” Id.
Asserting the government has not provided a “summary of his testimony,
and there are no reports containing this information,” defendants argue they
have “no idea what other assertions or opinions Gromer will render.” Id. at
p. 2. In the context of Facebook, defendants are concerned “[i]nterpretation is
inherently subjective, and may invade the province of the jury to make
assessments as to what various terms or phrases mean within the context of
the record.” Id. Defendants argue the witness lacks the expertise to
interpretate the Facebook records in this case. Id.
Ruling
“Facebook is a worldwide social networking company that: (i) builds tools
that enable users to connect, share, discover, and communicate with each
other; (ii) enables developers to build social applications of Facebook or to
integrate their websites with Facebook; and (iii) offers products that enable
advertisers and marketers to engage with its users.” In re Facebook, Inc., IPO
Sec. & Derivative Litig., 288 F.R.D. 26, 31 (S.D.N.Y. 2012). “As of February 2,
2012, Facebook had 845 million monthly users and 443 million daily users.”
Id.
Since approximately 2015, S.A. Gromer testified many times in this
court’s criminal jury trials. His testimony included areas as to the accuracy
and completeness of an application such as Facebook to produce its records
pursuant to a search warrant, explanations of the contents of Facebook and
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other applications which, in the court’s view, were beyond the ordinary
experience of jurors’ involvement with those applications. Coupled with his
familiarity with the investigation in this case, S.A. Gromer’s training and
experience may permit him to identify the defendants and others on Facebook.
The agent’s reliability may be established through personal experience and
knowledge. See United States v. Beltran-Arce, 415 F.3d 949, 951-52 (8th Cir.
2005) (“Federal Rule of Evidence 702 permits a district court to allow testimony
of a witness whose knowledge, skill, training, experience, or education will
assist the trier of fact in understanding an area involving specialized subject
matter.”); United States v. Peebles, 883 F.3d 1062, 1069-70 (8th Cir. 2018);
The capture of live videos and the authorship of the public posting of
videos on Facebook are, in the court’s view, examples of technological
information beyond the life experiences of an ordinary lay juror. S.A. Gromer’s
CV indicates he has been a presenter “to over 5000 people on Internet Safety/
Digital Evidence since 2010.” (Docket 488-1 at p. 8). If Facebook and the
other applications on the internet were matters of common knowledge, S.A.
Gromer would not need to expose thousands of individuals, whether lay or law
enforcement, to internet safety and digital evidence.
The court finds S.A. Gromer’s education, knowledge and experience on
internet applications and programs is extensive and includes experience in
tracking internet protocol (“IP”) addresses, Facebook originations and
authorship used to upload files, photographs and other information associated
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with a user’s access on the Facebook application through a computer, laptop,
iPhone or Android phone.
S.A. Gromer’s specialized knowledge and testimony will assist the jury in
understanding the Facebook evidence in this case. Daubert, 509 U.S. at 592;
Geddes, 844 F.3d at 991. After the government adduces sufficient evidence to
support a finding the agent’s Facebook testimony is relevant and admissible,
each defendant “remains free to challenge the reliability of the evidence, to
minimize its importance, or to argue alternative interpretations of its meaning,
but these and similar other challenges go to the weight of the evidence—not to
its admissibility.” United States v. Vayner, 769 F.3d 125, 131 (2d Cir. 2014)
(emphasis omitted). Defendants’ Daubert challenges to S.A. Gromer’s
testimony are denied.
Defendants’ contention that no report has been provided to them as part
of the government’s notice is misplaced. Rule 16 requires only that “the
government must give the defendant a written summary of any testimony that
the government intends to use under Rule[] 702 . . . of the Federal Rules of
Evidence during its case-in-chief at trial.” Fed. R. Crim. P. 16(a)(1)(G). “The
summary provided . . . must describe the witnesses opinions, the bases and
reasons for those opinions, and the witness’s qualifications.” Id.
The court finds the government’s notice, summary of the witness’
testimony and CV comply with the requirements of Rule 16(a)(1)(G).
Defendants’ objection to the government’s notice is overruled.
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ORDER
Based on the above analysis, it is
ORDERED that the defendants’ Daubert challenges to S.A. Gromer
(Dockets 579 & 587) are denied.
Dated September 8, 2021.
BY THE COURT:
/s/ Jeffrey L. Viken
JEFFREY L. VIKEN
UNITED STATES DISTRICT JUDGE
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