FILED
                                                                     United States Court of Appeals
                                        PUBLISH                              Tenth Circuit

                      UNITED STATES COURT OF APPEALS                         July 24, 2018
                                                                         Elisabeth A. Shumaker
                            FOR THE TENTH CIRCUIT                            Clerk of Court
                        _________________________________

 UNITED STATES OF AMERICA,

       Plaintiff - Appellee,

 v.                                                            No. 17-2085

 SHANE ROACH,

       Defendant - Appellant.
                      _________________________________

                     Appeal from the United States District Court
                           for the District of New Mexico
                          (D.C. No. 1:15-CR-02732-JAP-1)
                       _________________________________

Aric G. Elsenheimer, Assistant Federal Public Defender, Office of the Federal Public
Defender for the District of New Mexico, Albuquerque, New Mexico, for Defendant –
Appellant.

James R.W. Braun, Assistant United States Attorney (James D. Tierney, Acting United
States Attorney, on the brief) Office of the United States Attorney for the District of New
Mexico, Albuquerque, New Mexico, for Plaintiff – Appellee.
                         _________________________________

Before MATHESON, MCKAY, and MCHUGH, Circuit Judges.
                 _________________________________

MATHESON, Circuit Judge.
                   _________________________________

       A jury convicted Shane Roach of coercing D.G. into prostitution in violation of

18 U.S.C. § 1591(a)(1). Mr. Roach recruited D.G. and, with help from Angela
Santillanes, prostituted D.G. to clients. D.G. became scared and reached out for help,

leading to Mr. Roach’s and Ms. Santillanes’s arrests.

       The Government charged Mr. Roach and Ms. Santillanes under § 1591(a)(1), but

after Ms. Santillanes agreed to testify against Mr. Roach, it dropped her charge. At trial,

Mr. Roach attempted to cross-examine Ms. Santillanes about three topics. The

Government successfully objected.

       On appeal, Mr. Roach argues that the district court’s rulings preventing cross-

examination violated (1) the Confrontation Clause and (2) the Federal Rules of Evidence,

and because these errors were not harmless, we must vacate his conviction and remand

for a new trial.

       Exercising jurisdiction under 28 U.S.C. § 1291, we affirm Mr. Roach’s conviction

because (1) Mr. Roach waived his Confrontation Clause arguments, and (2) any error in

limiting his cross-examination under the evidence rules was harmless.

                                   I. BACKGROUND

                                    Factual Background

   The Prostitution Operation

       In April 2015, Mr. Roach found D.G.’s advertisement on Backpage.com

(“Backpage”), a website where prostitutes solicit clients, and offered to be her pimp. On

their second in-person meeting, she agreed.

       From May to June 2015, Mr. Roach and Ms. Santillanes managed the prostitution

operation, advertising D.G.’s services on Backpage and arranging for her to meet clients

in motels and hotels. Clients scheduled an appointment through “Diamond”—Ms.

                                              2
Santillanes’s alias—who then would inform Mr. Roach. He would then contact D.G.

through a prepaid TracFone he bought for her. The client would meet D.G. in her room,

and she would collect payment after the sex act. She saw three to six clients a day. Mr.

Roach would then collect the money from her.

       Mr. Roach controlled the enterprise and D.G.’s activities. He chose her rates,

selected her clients, and kept the proceeds. D.G. testified that he controlled her contact

with others, in part by keeping her identification (e.g., driver’s license) and her personal

cellphone. In his testimony, Mr. Roach disputed the level of control he had outside of

client matters.

   The Arrests and Search

       In June 2015, D.G. started to fear that Mr. Roach was going to send her to another

pimp. She notified Life Link, an organization that offers “program[s] for victims of

human trafficking.” ROA, Vol. III at 514. It contacted the Albuquerque Police

Department. 1 Police then contacted D.G., and she eventually disclosed her location. The

police removed her from her motel room and interviewed her. She divulged Mr. Roach’s

first name, identified him in an online photograph, and identified his car.

       After further investigation, officers obtained a warrant to track and search Mr.

Roach’s car and to search his residence. After tracking his car’s location, they stopped it,

discovered Mr. Roach and Ms. Santillanes inside, and arrested them. Executing the



       1
        D.G. testified that she had also contacted the police, but the testifying detective
did not mention her call at trial.

                                              3
search warrant, law enforcement searched Mr. Roach’s Albuquerque apartment and

found prepaid gift cards that had been used to purchase advertisements on Backpage. 2

                                   Procedural Background

   First Indictment, Government Deal, and Superseding Indictment

       In July 2015, a grand jury indicted Mr. Roach and Ms. Santillanes on one count of

sex trafficking by means of force, threats, fraud, and coercion in violation of 18 U.S.C.

§ 1591(a)(1). The Government made a deal with Ms. Santillanes: she agreed to testify

against Mr. Roach in exchange for having her charge dismissed. In April 2016, a

superseding indictment charged Mr. Roach alone with violating § 1591(a)(1). 3

   Pretrial Motions

       Mr. Roach filed a pretrial motion to cross-examine Ms. Santillanes regarding her

dismissed charge. He also filed a set of three pretrial motions to cross-examine Ms.

Santillanes about her prior and current involvement in prostitution. The district court

granted Mr. Roach’s first motion and denied the others. 4




       2
         Officers also discovered heroin; a digital camera with photos of D.G.’s
identification and photos used for her Backpage advertisement; and a .22 caliber firearm,
which D.G. identified as Mr. Roach’s.
       3
        In the superseding indictment, the Government originally charged Mr. Roach
with two counts of sex trafficking under § 1591(a)(1): trafficking (1) D.G. between
May 27, 2015 and June 11, 2015 and (2) Ms. Santillanes between March 1, 2015 and
June 11, 2015. Before trial, the Government dismissed the second count.
       4
       We describe these motions in greater detail in our discussion of Mr. Roach’s
Confrontation Clause arguments.

                                             4
   Trial Testimony

       Mr. Roach’s trial spanned four days. This appeal concerns the testimony of three

witnesses: D.G., Ms. Santillanes, and Mr. Roach. We provide an overview of their

testimony here. 5

       a. D.G.

       D.G. testified about her initial meeting with Mr. Roach, day-to-day activities

working for him, and her escape. She also testified about specific instances when Mr.

Roach was controlling and violent, stating that he isolated her from the outside world

using violence, intimidation, and threats.

       b. Ms. Santillanes

       Ms. Santillanes corroborated much of D.G.’s testimony. She confirmed that Mr.

Roach had been both controlling and violent toward D.G. The district court limited

defense counsel’s cross-examination on three lines of questioning: (1) the length of Ms.

Santillanes’s potential sentence under 18 U.S.C. § 1591(a)(1), (2) lying to her pretrial

services officer about residing with her grandparents, and (3) her potential fraud scheme

with the prepaid gift cards discovered in Mr. Roach’s apartment. Mr. Roach contests

these limitations on appeal.

       c. Mr. Roach

       Mr. Roach confirmed that he, Ms. Santillanes, and D.G. had engaged in a

commercial prostitution enterprise, but he denied controlling D.G. through violence,


       5
       We describe their testimony in greater detail in our discussion of Mr. Roach’s
Confrontation Clause and rules of evidence arguments.
                                             5
intimidation, and threats. He disputed D.G.’s testimony about specific instances of

violence and intimidation, but did admit that he hit her at least once. He characterized

their professional relationship as consensual and supportive.

   The Verdict and Sentence

       The jury found Mr. Roach guilty. The district court imposed a sentence of 180

months in prison. Roach filed this timely appeal.

                                    II. DISCUSSION

       On appeal, Mr. Roach argues that the district court improperly barred his

cross-examination of Ms. Santillanes on the three topics identified above.

       First, he argues the district court violated the Confrontation Clause because it

“limited [his] cross-examination of Ms. Santillanes to such an extent that the jury did not

receive sufficient information to make a discriminating appraisal of Ms. Santillanes’[s]

motives and bias.” Aplt. Br. at 36. We hold that Mr. Roach waived his Confrontation

Clause arguments because he failed to raise them below and did not argue plain error on

appeal.

       Second, he argues in the alternative that the court abused its discretion under the

Federal Rules of Evidence. See Aplt. Reply Br. at 4. But even assuming a rules

violation, we hold any error was harmless.

       We therefore affirm Mr. Roach’s conviction. 6


       6
        We address Mr. Roach’s Confrontation Clause arguments first and then turn to
his evidence-rules arguments. Mr. Roach primarily raises constitutional arguments on
appeal. Briefing on his nonconstitutional arguments is sparse.

                                             6
                                     Confrontation Clause

       Mr. Roach not only failed to make a Confrontation Clause argument below, his

failure to argue plain error here waives this issue on appeal.

   Additional Factual Background

       We first provide additional background on (a) Mr. Roach’s pretrial motions and

(b) defense counsel’s cross-examination at trial.

       a. Pretrial motions

              i. First pretrial motion

       Mr. Roach filed a “motion to allow cross-examination of D.G. and [Ms.

Santillanes] regarding outstanding dismissed without prejudice charges.” ROA, Supp.

Vol. I at 44 (capitalization omitted). He stated that Ms. Santillanes was “initially charged

as a codefendant . . . regarding . . . the charge of sex trafficking involving D.G.,” but the

Government “moved to dismiss the charge against [her].” 

He argued that he

should be allowed to question Ms. Santillanes about her motivations for testifying. 

He made no mention of his Sixth Amendment right to confrontation nor a relevant

Federal Rule of Evidence, but instead cited two cases. 

v. United States,

, 362 (5th Cir. 1978) and United States v. Harris, 

, 1035

(10th Cir. 1972)). Neither case concerned allegations of a Confrontation Clause

violation. The district court granted the motion.

              ii. Other pretrial motions

       Mr. Roach also filed three motions in limine to cross-examine Ms. Santillanes

about (1) her promoting prostitution in the present case and previously in the states of

                                              7
Arizona, New Mexico, and Texas; (2) prostituting an individual in a related case; (3) her

conviction for prostitution in Arizona; (4) prostituting herself while living with Mr.

Roach; and (5) answering phone calls for Mr. Roach about D.G.

       In each motion, he argued that exclusion of the questioning would violate his right

to confrontation. Because, Mr. Roach contended, the questioning would reveal Ms.

Santillanes’s biases, prejudices, and motives, he had a right under the Confrontation

Clause to cross-examine her on these five topics. He also relied on Federal Rules of

Evidence 404(b), 412, and 608. The district court denied the three motions.

       b. Trial cross-examination

       At trial, defense counsel attempted to cross-examine Ms. Santillanes about the

three aforementioned topics. The Government objected, and the district court sustained

the objections.

              i. Length of sentence

       After asking Ms. Santillanes about her dropped charge, defense counsel cross-

examined her about the length of her potential sentence:

              [Defense Counsel]: And that was quite a break, because
              before that happened, you were facing a pretty lengthy prison
              sentence, right?

              [Government]: Objection. Ask that we approach.
              The Court: Go ahead and state your objection.
              [Government]: We’re getting into punishment which I
              believe is not permissible evidence.

              The Court: That’s correct. That’s an incorrect form to
              inform the jury that there is a severe punishment.

                                             8
ROA, Vol. III at 407-08. Defense counsel agreed with the court’s statement and

explained that he “wasn’t attempting to introduce anything about [Mr. Roach’s] potential

punishment,” but rather “[his] question was aimed toward [Ms. Santillanes’s]

understanding, her motivation to testify falsely.” 

The court instructed counsel

to “avoid any questions about punishment,” 

the jury to disregard the

question, 

Defense counsel did not pursue this matter further. He did not

mention the Confrontation Clause.

              ii. Statement to pretrial services officer

       Before defense counsel resumed cross-examination of Ms. Santillanes on the

second day of trial and before the jury returned to the courtroom, he requested “to

cross-examine Ms. Santillanes on lying to her pretrial services officer.” 

The

proposed cross-examination was based on her attorney’s having filed a pretrial motion

stating her grandparents were willing to serve as her third-party custodians after the

Government dropped her charges. 

contended that when the

probation officers “went to go visit [her grandparents, they] told them she had not stayed

with them, and furthermore that she would not have permission to stay with them if she

had asked.” 

objected to this request, arguing it would elicit “improper

impeachment evidence under any of the rules.” 

stated that Ms.

Santillanes “didn’t lie” and explained:

              What happened is that her original plan was to stay with those
              people, and when she got up here, they told her that they
              wouldn’t allow her to stay with them, so she was staying with

                                              9
                a third party that she was not authorized to be. But there isn’t
                criminal conduct in any way. And at best, it could be
                described as a misunderstanding between the probation
                officer and Ms. Santillanes.

       The district court agreed with the Government and stated that it was “familiar with

what happened because she was under pretrial supervision, and reports were sent to me

from pretrial services.” 

“[I]f that testimony were allowed, [Ms. Santillanes]

would probably try to explain . . . what happened, and it might result in others having to

be called as witnesses to testify.” 

not] think it [was] proper impeachment.”

said nothing further on the issue.

                iii. Prepaid gift cards

       Finally, defense counsel questioned Ms. Santillanes about her collection of used

prepaid gift cards:

                [Defense Counsel]: And would you save all of those credit
                cards 7 even after there was no money left on them?

                [Ms. Santillanes]: Yes.

                [Defense Counsel]: Why?

                [Ms. Santillanes]: Because there may have been something
                that myself and [Mr. Roach] were interested in doing after the
                prostitution.

                [Defense Counsel]: Well, this thing you were talking about
                that you were interested in, [Mr. Roach] didn’t know anything
                about it, right?



       7
           Counsel was referring to prepaid gift cards as credit cards.

                                               10
              [Ms. Santillanes]: No, but he showed a lot of interest in it, so
              we started talking about it together, and what we could do
              with it.
              [Defense Counsel]: And you were essentially instructing
              [Mr. Roach] on how to commit fraud, right?

At that point, the Government objected as to relevance. 

Defense counsel explained that Ms. Santillanes “was interested in perpetrating some sort

of a fraud . . . . [s]o it goes to her credibility.” 

argued that the

deadline had passed for Rule 404(b) evidence and it could not evaluate this line of

inquiry without adequate notice. 

       The district court then asked how this cross-examination would impeach Ms.

Santillanes’s testimony because she would be “talking about a crime that [had not been]

committed.” 

Counsel responded:

              [W]hat I was talking about, and this went along testimony I
              was developing, that [Ms. Santillanes] was the one that knew
              all about the criminal activity, and she would teach [Mr.
              Roach] about that.

then said that counsel had already developed that point because Ms.

Santillanes had testified to teaching Mr. Roach about the prostitution business. 

that the evidence was inadmissible “under the language of 404(b)” and that

defense counsel should “stay away from it.” 

did not argue further.

   Legal Background

       We provide legal background on (a) offers of proof to preserve an objection for

appeal, (b) offers of proof in the context of limitations on cross-examination, and

(c) waiver.


                                               11
       a. Offers of proof

       To preserve an objection to the exclusion of evidence for appeal, the proponent

must make an offer of proof at trial, “first, describ[ing] the evidence and what it tends to

show and, second, identify[ing] the grounds for admitting the evidence.” United States v.

Adams, 

, 1241 (10th Cir. 2001); see also Fed. R. Evid. 103(a)(2). This is

so unless the nature of the excluded evidence and the ground for admitting it was

“apparent from the context.” 

(quotations omitted); see also

Fed. R. Evid. 103(a)(2). 8 “Unless the context in which evidence is offered makes clear

the reason for the proffer, error cannot be assigned to the exclusion of evidence without

an offer of proof.” United States v. Martinez, 

, 1485 (10th Cir. 1985).

       The proponent may present the offer in his questioning and objections at trial, see

, motions in limine, see United States v. Mejia-Alarcon, 

, 988 n.3 (10th Cir. 1993), or pretrial conferences, see Frederick v. Swift Transp.

Co., 

, 1083 (10th Cir. 2010).




       8
         Rule 103(a)(2) provides that “if the ruling excludes evidence, a party informs the
court of its substance by an offer of proof, unless the substance was apparent from the
context.” The provision does not mention, as our Adams case does, that the offer of proof
must not only describe the evidence but also identify the grounds for admitting it. The
advisory committee notes to Rule 103(a) make clear, however, that “[r]ulings on
evidence cannot be assigned as error unless (1) a substantial right is affected, and (2) the
nature of the error was called to the attention of the judge.” Fed. R. Evid. 103(a)
advisory committee’s note to 1972 proposed rules.

                                             12
         b. Limitations on cross-examination

         An offer of proof is generally necessary to preserve an excluded line of cross-

examination questioning. “Federal Rule 103 does not carve out any exception for

questions posed on cross.” McCormick on Evidence ch. 6, § 51, at n.17 (Kenneth S.

Broun ed., 7th ed. 2016). In United States v. Martinez, we determined the defendant

failed to preserve his argument that the district court improperly limited his cross-

examination of a government 

. On appeal, the defendant

asserted that the district court should have allowed the cross-examination under Federal

Rules of Evidence 404(b) and 406, but “[n]o offer of proof was made, and the trial judge

was not given any indication of defendant’s presently expressed purpose for his inquiry.”

Because defense counsel did not tell the judge the evidentiary ground nor

“the reason for the cross-examination,” he failed to preserve his challenge for appeal. 

1486.

         When a district court restricts cross-examination at trial, the party seeking to

cross-examine forfeits a challenge on appeal by failing to state the ground for objection,

id.; stating a different ground at trial than on appeal, United States v. Gramajo, 565 F.

App’x 723, 727 n.2 (10th Cir. 2014) (unpublished) (cited for persuasive value under Fed.

R. App. P. 32.1, 10th Cir. R. 32.1); United States v. Faruki, 

, 856 (7th Cir.

2015); United States v. Reaves, 

, 865 (8th Cir. 2011); or by failing at trial to

object to the limitation at all, United States v. Mullins, 

, 1283 (10th Cir.

2010).



                                               13
       c. Waiver

       An appellant who fails to preserve an evidentiary objection below may argue and

establish plain error on appeal, United States v. LaHue, 

, 1009 (10th Cir.

2001), by showing that the “district court committed (1) error (2) that is clear or obvious

under current law, and which both (3) affected her substantial rights and (4) undermined

the fairness, integrity, or public reputation of judicial proceedings,” 

. Failure to argue plain error on appeal waives the argument. United States v.

Solomon, 

, 1238 (10th Cir. 2005); United States v. MacKay, 

,

831 (10th Cir. 2013).

   Analysis

       a. Mr. Roach failed to raise a Confrontation Clause objection below

       Mr. Roach failed to raise the Confrontation Clause issue below for all three lines

of questioning, either at trial or in his pretrial motions. To preserve the issue, he needed

to describe (1) the evidence and (2) the ground to admit it. See 

.

He failed to do the former in his pretrial motions and the latter at trial.

       As previously explained, Mr. Roach’s Confrontation Clause arguments concern

the district court’s refusal to allow his lawyer to cross-examine Ms. Santillanes about

(1) the length of her potential sentence under 18 U.S.C. § 1591(a)(1), (2) her alleged lie

to her pretrial services officer, and (3) her possible alleged scheme to use the prepaid gift

cards for fraud. In his pretrial motions, Mr. Roach failed to identify any of these three

topics for cross-examination.

       In his first motion, he argued that he should be allowed to question Ms. Santillanes

                                              14
about her deal with the Government. But he did not mention the length of her potential

sentence under 18 U.S.C. § 1591(a)(1) as a cross-examination topic. 9 In his other three

motions, he argued that he should be able to cross-examine Ms. Santillanes about her

prior and current participation in prostitution under his constitutional right to

confrontation, but he did not mention any of the three topics he raises on appeal. 10

       Although Mr. Roach is correct that he need not “specifically mention[] the

Confrontation Clause” when it is apparent from the context, Aplt. Br. at 40; see 

, he must also assert the particular topic for cross-examination, see

United States v. Summers, 

, 1297 n.7 (10th Cir. 2005) (preserving the


       9
          Moreover, he did not mention his right to confrontation under the Sixth
Amendment as a ground for cross-examination about her deal.
        Mr. Roach cites United States v. Szabo, 

(10th Cir. 1986), to argue
that he sufficiently preserved the constitutional argument in his first pretrial motion, but
Szabo is distinguishable. In Szabo, the defendant had filed a motion in limine arguing
that a government witness’s statements “ha[d] no indicia of reliability and [did] not
provide the functional equivalent of cross-examination.” 

        We addressed his Confrontation Clause argument on appeal because “the
constitutional issue was at least arguably raised at one time during the proceedings below,
by way of the motion in limine,” 

in that it contained the phrase “indicia of
reliability,” the Confrontation Clause standard at the time for admitting hearsay evidence
for an unavailable declarant.
        Here, Mr. Roach’s motion in limine did not “arguably raise[]” a Confrontation
Clause claim with respect to the length of sentence. It not only failed to mention the
Confrontation Clause or its underlying standard, it also did not mention the length of the
sentence as a topic for cross-examination.
       10
         As mentioned above, the three motions requested the opportunity to cross-
examine Ms. Santillanes about (1) her promoting prostitution in the present case and
previously in the states of Arizona, New Mexico, and Texas; (2) prostituting an
individual in a related case; (3) her conviction for prostitution in Arizona; (4) prostituting
herself while living with Mr. Roach; and (5) answering phone calls for Mr. Roach about
D.G.

                                              15
constitutional argument by demanding cross-examination of co-defendant’s hearsay

statement at trial); United States v. Szabo, 

, 1487 (10th Cir. 1986)

(preserving the constitutional argument by requesting cross-examination of

co-conspirator’s hearsay statements in a motion in limine). In his pretrial motions, Mr.

Roach failed to raise the length of Ms. Santillanes’s potential sentence, the alleged lies to

her pretrial services officer, and the alleged prepaid card scheme.

       When Mr. Roach did raise these issues at trial, he failed to state a Confrontation

Clause ground on which the court should permit the cross-examination. Indeed, Mr.

Roach concedes that he “did not mention the Confrontation Clause at trial,” Aplt. Reply

Br. at 3, but argues he sufficiently raised his constitutional arguments in his pretrial

motions. He claims that he “repeatedly stress[ed] . . . the constitutional basis for his

requests for cross-examination of Ms. Santillanes on various topics,” and that any

restriction on such questioning “would violate the Confrontation Clause.” Aplt. Br.

at 39-40. We disagree. Although he mentioned the Confrontation Clause in his second

set of pretrial motions, he neglected to mention the three topics for cross-examination in

any of his pretrial motions. It was therefore not “apparent” when he pursued cross-

examination on these topics at trial that he was relying on the Confrontation Clause.

. 11


       11
          Mr. Roach also argues that “the combination of Mr. Roach’s frequent pretrial
assertions of his constitutional right to cross-examination, the district court’s recognition
of that right and Mr. Roach’s objections to curtailing his cross-examination during trial
preserved the Confrontation Clause issues.” Aplt. Br. at 41. But because his pretrial
motions failed to identify any of the cross-examination topics he wished to pursue at trial
and now on appeal, and because he failed to object based on confrontation regarding
                                              16
       In sum, because Mr. Roach neither mentioned the three topics in his pretrial

motions nor the Confrontation Clause at trial, he forfeited his arguments below.

       b. Mr. Roach fails to argue plain error on appeal

       Mr. Roach fails to argue plain error on appeal. He therefore has waived his

Confrontation Clause arguments about the three lines of questioning and we do not

consider them further. See 

; 

.

                                       Rules of Evidence

       Mr. Roach argues “even assuming arguendo [he] did not preserve the cross-

examination restrictions as constitutional issues, he preserved them for non-constitutional

review under the abuse-of-discretion standard.” Aplt. Reply Br. at 4. He contends the

district court abused its discretion under the Federal Rules of Evidence when it prevented

him from cross-examining Ms. Santillanes on the three topics.

       Although we question whether Mr. Roach adequately preserved his

nonconstitutional objections, we need not address that issue nor whether the district court

abused its discretion. Even assuming the district court abused its discretion, any error

was harmless.

   Legal Background

       “A party may claim error in a ruling to . . . exclude evidence only if the error

affects the substantial right of the party . . . .” Fed. R. Evid. 103(a). “The rule does not



these topics at trial, we do not discern an adequate contextual ground, and certainly not a
“clear” one, 

, for Mr. Roach to overcome his forfeiture of his
Confrontation Clause arguments.

                                              17
purport to change the law with respect to harmless error.” Fed. R. Evid. 103(a) advisory

committee’s note to 1972 proposed rules.

       “We will not reverse a defendant’s conviction on the basis of a district court’s

erroneous admission [or exclusion] of evidence if the error was harmless to the

defendant.” United States v. Kupfer, 

, 1243 (10th Cir. 2015); see United

States v. Irving, 

, 1209 (10th Cir. 2011) (applying to excluded evidence).

“A non-constitutional error is harmless unless it had a ‘substantial influence’ on the

outcome or leaves one in ‘grave doubt’ as to whether it had such effect.” United States v.

Rivera, 

, 1469 (10th Cir. 1990) (en banc) (quoting Kotteakos v. United

States, 

, 765 (1946)). “To make this assessment, we review the entire record

de novo, examining the context, timing, and use of the erroneously admitted [or

excluded] evidence at trial and how it compares to properly admitted evidence.” 

(quotations omitted). The government bears the burden to show that a

nonconstitutional error is harmless by a preponderance of the evidence. See United

States v. Jones, 

, 1101 (10th Cir. 2016).

   Analysis

       Mr. Roach argues the district court’s limitations on cross-examination had a

“substantial influence on the verdict.” Aplt. Br. at 55. But for three reasons, the




                                             18
Government has demonstrated that the limitations—individually or cumulatively 12—did

not substantially influence the outcome of the case. 13

       First, Mr. Roach challenged Ms. Santillanes’s credibility throughout the cross-

examination. Defense counsel questioned her about her past methamphetamine use and

how she was still testing positive for drugs a year after charges had been brought in this

case. He also asked her about “not telling [Mr. Roach] that you were actively

prostituting” when she was romantically involved with him, which “was a pretty big lie,

right?” ROA, Vol. III at 403. Most important, he inquired about the deal she made with

the Government to testify. Although the district court blocked questions about the length

of the potential sentence, counsel was able to ask about her charges being dropped in

return for her testimony.

       Second, Mr. Roach called two witnesses to impeach Ms. Santillanes’s character

for truthfulness. He questioned Vanessa Baca, who “ha[s] children with [Mr. Roach’s]



       12
         To the extent Mr. Roach attempts to present a cumulative error argument
regarding the restrictions on the three lines of questioning, “we aggregate all the errors
that we have found to be harmless and determine whether their cumulative effect on the
outcome of the trial mandates reversal.” United States v. Anaya, 

, 1060-61
(10th Cir. 2013) (quotations omitted). For the reasons presented above, we conclude that
any evidence-rules errors, considered individually or together, did not substantially affect
the outcome of the trial. See 

       13
          The Government primarily argues that any constitutional error—as opposed to
nonconstitutional error—was harmless. As it recognizes, the standard for a harmless
constitutional error is whether we are “able to declare a belief that it was harmless
beyond a reasonable doubt.” 

(quoting Chapman v. California,

, 24 (1967)). This standard requires more from the Government than showing
a nonconstitutional error was harmless.

                                             19
cousin,” 

about her “opinion as to [Ms. Santillanes’s] truthfulness,” 

She responded that Ms. Santillanes was not truthful. Similarly, he asked Christopher

Baca, Mr. Roach’s former roommate, a similar question, and he gave the same answer.

See 

       Third, even assuming the blocked cross-examination would have put Ms.

Santillanes’s credibility into further doubt, it would not have substantially influenced the

outcome of the case. The jury had ample evidence to convict Mr. Roach without her

testimony. Under 18 U.S.C. § 1591(a)(1), the Government needed to prove that Mr.

Roach knowingly “recruit[ed], entice[d], harbor[ed], transport[ed], provide[d],

obtain[ed], advertise[d], maintain[ed], patronize[d], or solicit[ed]” D.G., knowing that

“means of force, threats of force, fraud, [or] coercion” would be used to “cause [her] to

engage in a commercial sex act.” 18 U.S.C. § 1591(a)(1). 14 D.G. described incidents in


       14
            Section 1591(a) reads in full:
                (a) Whoever knowingly—
                       (1) in or affecting interstate or foreign commerce, or
                       within the special maritime and territorial jurisdiction
                       of the United States, recruits, entices, harbors,
                       transports, provides, obtains, advertises, maintains,
                       patronizes, or solicits by any means a person; or
                       (2) benefits, financially or by receiving anything of
                       value, from participation in a venture which has
                       engaged in an act described in violation of
                       paragraph (1),
                knowing, or, except where the act constituting the violation of
                paragraph (1) is advertising, in reckless disregard of the fact,
                that means of force, threats of force, fraud, coercion described
                in subsection (e)(2), or any combination of such means will
                                               20
which Mr. Roach attacked or threatened her. For example, she testified that when he

learned she had been speaking with others on Facebook, he drove her to the outskirts of

Albuquerque. With a gun in his lap, he told her that he was disappointed with her

because she was talking to “a bunch of people.” ROA, Vol. III at 502-03. Mr. Roach

then slapped her face “multiple” times and warned that, if she left him, he would hurt one

of her family members. 

Mr. Roach disputed these episodes, but he did

testify to an occurrence when he hit D.G. He admitted to “slapp[ing] her with an open

hand once across her face,” 

because he believed that she was “still doing

side dates,” 

The evidence thus showed that Mr. Roach used violence to coerce

D.G. into prostitution.

       Even if we “are not totally free from doubt about whether” the limitations on

cross-examination “may have had some influence on the outcome of the case,” “we do

not have grave doubt that the errors,” alone or cumulatively, “had a substantial effect on

the outcome.” United States v. Charley, 

, 1270 n.29 (10th Cir. 1999)

(“Grave doubt, by definition, does not refer to every level of doubt, and substantial

influence, by definition, does not mean any or some influence.”). Assuming that the

district court abused its discretion in limiting cross-examination, any errors were

harmless because they did not have a substantial influence in the outcome of the case.


              be used to cause the person to engage in a commercial sex
              act, or that the person has not attained the age of 18 years and
              will be caused to engage in a commercial sex act, shall be
              punished as provided in subsection (b).
18 U.S.C. § 1591(a).

                                             21
                                   III. CONCLUSION

       Mr. Roach’s challenge on appeal to the district court’s foreclosure of his three

lines of cross-examination fails. He has waived his Confrontation Clause arguments, and

any error under the rules of evidence was harmless. We uphold Mr. Roach’s conviction

and affirm the district court’s judgment.




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