NOT PRECEDENTIAL

                      UNITED STATES COURT OF APPEALS
                           FOR THE THIRD CIRCUIT
                                _____________

                                     No. 16-1844
                                    _____________

                          UNITED STATES OF AMERICA,
                                              Appellant
                                     v.

                           ANTHONY F. D’AMBROSIO
                        ANTONIO DELGADO, aka Little Tony
                         ARMANDO ENRIQUE DELGADO
                          KEANU DAVONE MARTINEZ
                               ______________

                    On Appeal from the United States District Court
                        for the Middle District of Pennsylvania
                  (D.C. Crim. No. 1-15-cr-00003-002, 003, 004 & 005)
                    District Judge: Honorable William W. Caldwell
                                    ______________

                              Argued: November 8, 2016
                                  ______________

     Before: McKEE, RESTREPO, Circuit Judges, and HORNAK, District Judge.*

                           (Opinion filed: January 26, 2017)
                                  ______________

Peter J. Smith
Stephen R. Cerutti II
Meredith A. Taylor [ARGUED]
United States Attorney’s Office
Middle District of Pennsylvania
Ronald Reagan Federal Building


      *
         Honorable Mark R. Hornak, District Judge for the United States District Court
for the Western District of Pennsylvania, sitting by designation.
Suite 220
228 Walnut Street
Harrisburg, PA 17108
       Counsel for Appellant

John A. Abom [ARGUED]
Abom & Kutulakis
2 West High Street
Carlisle, PA 17013
       Counsel for Appellee Anthony D’Ambrosio

Dean E. Reynosa
Griest Himes Herrold & Reynosa
129 East Market Street
York, PA 17401
       Counsel for Appellee Antonio Delgado

Robert J. Daniels
Killian & Gephart
218 Pine Street
P.O. Box 886
Harrisburg, PA 17108
       Counsel for Appellee Armando Delgado

Joseph Sembrot
Goldberg Katzman
4250 Crums Mill Road, Suite 301
P.O. Box 6991
Harrisburg, PA 17112
       Counsel for Appellee Keanu Martinez

                                     ______________

                                       OPINION**
                                     ______________
RESTREPO, Circuit Judge.

       The Government filed this interlocutory appeal from the District Court’s in limine


       **
          This disposition is not an opinion of the full Court and, pursuant to I.O.P. 5.7,
does not constitute binding precedent.

                                              2
ruling precluding the Government from calling an expert witness. We will affirm.

                                                I

       Appellees Anthony D’Ambrosio, Antonion Delgado, Armando Delgado and

Keanu Martinez are charged in a Superseding Indictment with, inter alia, sex trafficking

offenses, in violation of 18 U.S.C. §§ 1591, 2421, 2423 and 371. Prior to trial, the

Government provided notice that it intended to call an expert witness, Dr. Sharon Cooper,

to provide “background” on the “culture” of sex trafficking. App. 83. The Government

seeks to introduce this testimony to “de-mystify this subculture” and to provide

“education and context” for the jury. Br. for Appellant 7, 10. The Government does not

contend that the proffered testimony goes to any element of the charged offenses.

       Appellees moved in limine to preclude the Government’s expert, and the District

Court granted the motion. The District Court explained that the proffered expert

testimony was irrelevant under Federal Rule of Evidence 401. The District Court further

promised to revisit the issue based upon the testimony of the fact witnesses. The District

Court suggested that the Government may be permitted to call its expert after the fact

witnesses testify if a foundation is established.

                                                II

       The District Court had jurisdiction under 18 U.S.C. § 3231 and we have

jurisdiction under 18 U.S.C. § 3731. Our standard of review is abuse of discretion.

Sprint/United Mgmt. Co. v. Mendelsohn, 

, 384 (2008). This standard

reflects the fact that “[w]ith respect to evidentiary questions . . . a district court virtually

always is in the better position to assess the admissibility of the evidence in the context of

                                                3
the particular case before it.” 

see also In re TMI Litig., 

, 666 (3d

Cir. 1999).

                                               III

       The district courts serve a gatekeeping role to determine whether expert testimony

meets the requirements of Federal Rule of Evidence 702. Daubert v. Merrell Dow

Pharm., Inc., 

, 592-97 (1993). Rule 702 requires (1) that an expert witness

be qualified, (2) that the testimony be reliable and (3) that the testimony assist the fact-

finder. United States v. Schiff, 

, 172 (3d Cir. 2010).

       This case involves only the third requirement—“helpfulness” or “fit.” This

requirement is based upon the text of Rule 702, which requires that an “expert’s

scientific, technical, or other specialized knowledge . . . help the trier of fact to

understand the evidence or to determine a fact in issue.” Fed. R. Evid. 702(a). To be

helpful, expert testimony must be “sufficiently tied to the facts of the case that it will aid

the jury in resolving a factual dispute.” 

(quotation marks and

citation omitted). Conversely, “expert evidence which does not relate to an issue in the

case is not helpful.” United States v. Ford, 

, 219 n.6 (3d Cir. 2007)

(quotation marks and citation omitted). “The ‘standard is not that high,’ but ‘is higher

than bare relevance.’” 

(citation omitted). We caution the district

courts to “tread carefully when evaluating proffered expert testimony,” as “scientific

expert testimony carries special dangers to the fact-finding process because it can be both

powerful and quite misleading because of the difficulty in evaluating it.” 

n.6 (quotation marks and citations omitted).

                                               4
       Expert testimony on the culture of sex trafficking was the subject of a decision by

the Court of Appeals for the District of Columbia Circuit, United States v. Anderson, 

, 392 (D.C. Cir. 1988). Anderson held that a district court did not abuse its

discretion by admitting such testimony to rebut cross-examination suggesting that the

victims “travelled with [the defendant] quite voluntarily; and that they had not engaged in

prostitution at his direction.” 

These were “facts ‘that could be determinative

of [the defendant’s] guilt or innocence.’” 

see also United States v.

King, 

, 1075 (D. Haw. 2010) (admitting the testimony of Dr.

Cooper, but where the testimony bore “directly on an element” of eight counts). In other

cases, in contrast, courts have affirmed the exclusion of cultural experts. See, e.g., United

States v. Bostick, 

, 151 (D.C. Cir. 2015) (affirming exclusion of gang culture

expert as unhelpful because gang membership was not an element and not alleged);

United States v. Amawi, 

, 480 (6th Cir. 2012) (affirming exclusion of expert

on jihadist “cultural norms” where testimony would not help the jury in determining

whether the defendants committed the crimes charged); United States v. Abdush-Shakur,

, 466-67 (10th Cir. 2006) (affirming exclusion of prison culture expert

where testimony was irrelevant to the crimes charged).

       With such precedents in mind, we will affirm the decision of the District Court to

exclude the proffered expert. As in Bostick, Amawi and Abdush-Shakur, the proffered

testimony would not help the trier of fact in determining the defendants’ guilt as to the

offenses charged. Or, at the very least, the District Court did not abuse its discretion in so

holding.

                                              5
       Having reached this conclusion, we go on to note that the impact of our ruling may

be slight. The District Court has promised to revisit its decision based upon the

testimony of the fact witnesses. This decision, which “allows the Government to present

its fact witnesses at trial, and then petition the Court for introduction of [expert]

testimony, was a pragmatic solution and not an abuse of discretion.” 

. The District Court retains its discretion to reconsider the proffered evidence should

defense counsel open the door by way of cross-examination of witnesses or the

presentation of evidence that would make the expert opinion relevant.1

                                              IV

       We will affirm and remand for further proceedings consistent with this opinion.




       1
         Because we affirm under Rule 702, we need not determine whether some or all
of the expert testimony would be inadmissible under Rule 403. Cf. 

(expert testimony potentially unduly prejudicial).
                                               6