              Case: 17-14387    Date Filed: 08/19/2019   Page: 1 of 60


                                                                         [PUBLISH]

                IN THE UNITED STATES COURT OF APPEALS

                         FOR THE ELEVENTH CIRCUIT
                           ________________________

                            Nos. 17-14387, 18-12866
                           ________________________

                   D.C. Docket No. 6:17-cr-00045-CEM-DCI-1



UNITED STATES OF AMERICA,

                                                                 Plaintiff-Appellee,

                                       versus

JOHN DAVID STAHLMAN,

                                                               Defendant-Appellant.

                           ________________________

                   Appeals from the United States District Court
                        for the Middle District of Florida
                          ________________________

                                 (August 19, 2019)

Before JORDAN, GRANT and HULL, Circuit Judges.

HULL, Circuit Judge:

      After a jury trial, John David Stahlman appeals his conviction and 292-

month sentence for attempting to entice a minor to engage in sexual activity. On

appeal, Stahlman argues that the district court erred: (1) in excluding the testimony
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of his proposed expert, Dr. Chris Carr; (2) in admitting the case agent’s lay opinion

testimony and in denying Stahlman’s motion for a mistrial on that ground; (3) in

denying his motions for judgment of acquittal; (4) in imposing a sentencing

enhancement for obstruction of justice; and (5) in denying his post-trial motion for

a new trial. After review, and with the benefit of oral argument, we affirm.

      We begin by recounting the trial evidence about Stahlman’s offense conduct,

next review the procedural history, and then address Stahlman’s claims in turn.

                         I. FACTUAL BACKGROUND

      After two months of sordid email exchanges with a father who was offering

his 11-year-old daughter for sex, Stahlman drove to a parking lot to meet up and

live out his self-described “daddy/daughter fantasy.” Unfortunately for Stahlman,

the “father” was an undercover agent with the Federal Bureau of Investigation

(“FBI”), and the “daughter” did not exist. At trial, Stahlman testified and told the

jury that he believed all along that he was acting out a role-playing sexual game

with other adults—that he never intended to have sex with an actual minor, just an

adult pretending to be a minor. The jury found him guilty.

      Stahlman’s sordid conduct began on November 10, 2016, when he posted an

ad on the “Casual Encounters” section of the “Personals” page on Craigslist

entitled “Daddy/daughter fantasy,” with a picture of girl laying on a bed wearing

only underwear and a camisole. In the ad, Stahlman wrote: “I am a married white


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guy looking for a young ‘looking’ girl to play out some fantasies with me.”

Stahlman added: “I have a daughter but wouldn’t dare defile her. So I’d like to

chat at first to fill this need, and maybe, just maybe move to physical pleasure.”

Stahlman closed the ad by requesting that interested persons contact him via email

or the instant messaging application Kik and stating, “Hope to hear from you,

honey.”

      On November 16, 2016, Special Agent Rodney Hyre came across

Stahlman’s Craigslist ad while working in an undercover capacity to identify

persons who might be trying to sexually exploit children. Agent Hyre is the

coordinator of the FBI’s Violent Crimes Against Children Task Force. Agent Hyre

estimated the age of the girl pictured in Stahlman’s ad to be between 10 and 12

years’ old and suspected from “the nature of the advertisement” that Stahlman

might be someone who was “attempting to find a child to sexually exploit.”

Responding to the ad, Agent Hyre began an undercover conversation with

Stahlman. The conversation lasted from mid-November 2016 through the end of

January 2017. During that time, Stahlman and Agent Hyre exchanged 125 emails

and 22 Kik messages discussing plans for Stahlman to meet and engage in sexual

activity with Hyre’s fictional 11-year-old daughter.

      In his initial response to Stahlman’s post, Agent Hyre stated he was a

straight, single father of an 11-year-old daughter. Hyre indicated that he felt “the


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same way” Stahlman did and said “HMU [hit me up] if this interests you.”

Stahlman quickly responded: “Defin[i]tely interested. Depends on what you want

to do?” Agent Hyre asked about Stahlman’s daughter. Stahlman responded that

she was nine years’ old and reiterated that he “wouldn’t defile [his] little girl,” but

said, “I think I would play with someone else’s.”1 In another email, however,

Stahlman stated that he fantasized about his own daughter “[i]n the right

moments[,] when she is changing and I catch a glimpse or when we are tickle

fighting and hands go places.” Agent Hyre explained that, in this context “tickle

fighting” or the “tickle game” meant “where people interested in children this way

will pretend they’re tickling the child to make them laugh, and they will let their

hands drift into inappropriate places on the child to test the boundaries of the

child.”

       As the conversation progressed, Agent Hyre indicated to Stahlman that his

11-year-old daughter had engaged in sexual activities with other adult men before.

Stahlman stated that he “would like to act out [his] fantasies” and would like to

“play” with Hyre’s 11-year-old. Stahlman asked Agent Hyre: “So what would I

have to do to . . . ‘qualify’ myself the opportunity to meet your lovely little lady?”




       1
        After he arrested Stahlman, Agent Hyre discovered that Stahlman in fact did not have a
nine-year-old daughter.
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Agent Hyre replied that Stahlman would “have to be okay with me watching,” and

Stahlman agreed that he would be “totally ok” with that.

       Over the course of their conversations, Stahlman made several statements

describing the types of sexual activities he would like to engage in with Agent

Hyre’s 11-year-old daughter. Among other things, Stahlman stated: “I just

envisioned licking your daughter’s pussy as she slept and you filming it”; “I’d

defin[i]tely want to eat her pussy and watch her suck my cock. I’d probably want

to eat her little ass too”; “[I]f it led to sex I’d be cool with that too but I’m for sure

into oral play”; “I would like to see her undress, or undress her myself and just kiss

and play. Maybe do a little oral on eachother. Then see where it leads”; “I think I

would want sex, maybe even anal”; “[C]ould her and I start with a shower[?]”; and

“We could explore eachother’s bodies and it not be all that sexual. Then be all

clean for the fun part.” Stahlman also asked Agent Hyre for pictures of his 11-

year-old, and Agent Hyre sent him a picture of a fellow law enforcement officer

when she was 12 or 13. Stahlman commented that she was “a little older than [he]

pictured, which is quite alright,” and that “she looks very cute and sexy.”

       Stahlman attempted to set up a meeting with Agent Hyre and his 11-year-old

in mid-November while Stahlman’s wife was supposed to be out of town, but the

plan was cancelled when Stahlman’s wife insisted that he travel with her. A bit

later in November, Stahlman again discussed plans to meet Agent Hyre’s 11-year-


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old, but that plan likewise fell through when Stahlman was unable to get away

from his wife. In early December 2016, Agent Hyre reached out to Stahlman again

and asked, “Hey man you still interested in playing or should I delete you?”

Stahlman replied: “Go ahead and delete me. My availability has just dwindled

lately. It’s probably not gonna happen. Thanks for the opportunity.” When Agent

Hyre inquired whether Stahlman might “want to later” or had “just changed [his]

mind about the whole thing,” Stahlman replied that he had not changed his mind,

but could not find the time to set up a meeting.

      The conversation between Stahlman and Agent Hyre lapsed through the rest

of December 2016 and into January 2017, but picked back up when Agent Hyre

contacted Stahlman again in late January. In a January 23, 2017 email, Agent Hyre

stated: “Last we talked you said you hadnt changed your mind[.] Just couldnt find

the time, that still true[?]” Stahlman confirmed “that’s still true,” then asked “Are

you two free a week from now? Next Monday?” Agent Hyre responded that he

and his daughter would be available, and over the next few days, Hyre and

Stahlman made plans for their meeting.

      Ultimately, they decided to meet at 8:30 a.m. on Monday, January 30, 2017

in the parking lot of a Gander Mountain sporting goods store in Lake Mary,

Florida. Agent Hyre proposed that the two men meet each other first, then go to

meet Agent Hyre’s 11-year-old, and Stahlman agreed. Stahlman told Agent Hyre


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he would be driving a “[w]hite VW.” Among other things, Stahlman asked Agent

Hyre multiple times whether he should bring condoms, whether he could shower

with Agent Hyre’s daughter before engaging in sexual activity with her, whether

she “like[d] kissing,” and whether Agent Hyre would be filming or taking pictures

of their activities. On the day before the meeting, Stahlman told Agent Hyre “I am

really looking forward to Monday,” and “I can’t wait.” On the morning of January

30, 2017, about an hour before they were scheduled to meet, Stahlman emailed:

“Tik Tock. It’s almost time.”

      The morning of their scheduled meeting, January 30, 2017, Stahlman drove

to the Gander Mountain parking lot in Lake Mary from his home in Longwood,

Florida. Stahlman arrived at approximately 8:25 a.m. in his white VW, wearing a

green Teenage Mutant Ninja Turtles t-shirt. Stahlman exited his vehicle and

approached the undercover agent (not Agent Hyre) who was playing the role of the

father of the 11-year-old. At that point, Agent Hyre, who was watching from a

surveillance vehicle, approached and arrested Stahlman.

      Stahlman waived his Miranda rights and agreed to speak with Agent Hyre

and another agent, Kevin Kaufman. During the interview, Stahlman admitted that

he was in a conversation for the last two-and-a-half months with the father of an

11-year-old and that conversation was about Stahlman’s engaging in sex with the

11-year-old. Stahlman told Agent Hyre that he “knew that he could get arrested,


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he knew that this could have been a sting, but he came to the parking lot anyway.”

At one point during the interview, Stahlman told Agent Hyre that he “was there to

have sex with [Hyre’s] wife,” but later conceded that they had never “talked about

an adult woman a single time” and that there had been no mention of a wife or

other adult. Agent Hyre also noted that he had told Stahlman he did not need to

bring condoms because the 11-year-old was too young to get pregnant, and

Stahlman acknowledged that he “showed up without condoms because he believed

he was showing up for an eleven-year-old.” Stahlman also told Agent Hyre,

however, that he was expecting to meet an adult portraying a minor and referred to

their conversation as a “fantasy façade.”

                          II. PROCEDURAL HISTORY

      In 2017, a federal grand jury charged Stahlman with one count of attempting

to persuade, induce, and entice a minor to engage in sexual activity, in violation of

18 U.S.C. § 2422(b). Stahlman pled not guilty and proceeded to trial.

A.    Dr. Carr’s Testimony

      Prior to trial, Stahlman gave notice of his intent to present the testimony of

psychologist Dr. Chris Carr, Ph.D., as an expert witness. Stahlman sought to

introduce Dr. Carr’s testimony to “provide the proper context to Mr. Stahlman’s

fantasy ad and his subsequent communications.” Specifically, Dr. Carr would

“opine that Mr. Stahlman’s online communications at issue in this case, along with


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Mr. Stahlman’s history of sexual behavior, is consistent with a person attempting

to act out a fantasy rather than attempting sexual contact with an actual minor.”

      The government filed a motion in limine to exclude Dr. Carr’s testimony,

arguing that his testimony: would impermissibly give an opinion on Stahlman’s

intent, in violation of Federal Rule of Evidence 704(b); was not proper expert

testimony under Rule 702; was not relevant under Rule 401; and should be

excluded under Rule 403 because it carried an undue risk of misleading the jury.

      Stahlman responded that: Dr. Carr’s testimony was necessary to ensure his

right to present a defense; that Dr. Carr was qualified to provide expert testimony

based on his professional training and experience; that other courts have admitted

expert testimony similar to Dr. Carr’s; that Dr. Carr’s testimony would help the

jury understand the concept of internet-based sexual fantasy; and that Dr. Carr’s

testimony would not violate Rule 704(b).

      The district court held an evidentiary hearing on the government’s motion to

exclude Dr. Carr’s testimony. At the hearing, Dr. Carr testified that he was a

licensed psychologist since 1994, worked as a forensic psychologist for his entire

career, and focused on evaluating people who had committed sex offenses.

Dr. Carr previously worked for the Florida Department of Corrections for six

years. Since 2003, Dr. Carr worked for the State of Florida as a member of the

Department of Children and Families Sexually Violent Predator Program. As part


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of that program, Dr. Carr conducted evaluations of the “highest risk” sexual

offenders to determine whether they should be civilly committed after completing

their prison terms.

      Dr. Carr met with Stahlman in March 2017 and conducted a diagnostic

interview. As part of his evaluation, Dr. Carr took Stahlman’s “psychosocial and

psychosexual history,” reviewed Stahlman’s Craigslist ad and conversations with

Agent Hyre, and consulted relevant journal articles. Dr. Carr believed Stahlman

was “open” and truthful during their interview and provided “abundant

information” to inform his diagnosis. Dr. Carr diagnosed Stahlman with moderate

adjustment disorder with anxiety and “other specified sexual dysfunction,” which

Dr. Carr described as “qualified bisexual preoccupation and sexual fantasy online.”

      Dr. Carr opined that, in this case, Stahlman “was engaged in role-playing

and fantasy role-play.” Dr. Carr based this opinion on Stahlman’s history, the

Craigslist ad and emails, the DSM-V, and “research articles about this type of

phenomena.” In particular, Dr. Carr relied on two articles, “Typing, Doing and

Being: Sexuality and the Internet,” and “The Online Disinhibition Effect,” which

Dr. Carr stated were peer-reviewed and written by authors who are experienced

and well-respected in this area.

      Dr. Carr explained that there is a difference between a desire to engage in

role-play and a desire actually to engage in sexual activity with a minor. Dr. Carr


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elaborated that, with a daddy-daughter fantasy for example, there are two ways of

seeking that out. One way “is to go to child pornography sites [where] you would

find that kind of thing.” The other would be to act out the fantasy with other

adults. Dr. Carr opined that, with “people who have sexual interest in a child, it’s

about the child’s body, whereas with adults acting out these types of fantasies, it’s

more about the psychological dynamics involved.” In other words, in the fantasy

context, “your sexual interest is in adults playing certain roles.”

      On cross-examination, Dr. Carr acknowledged that he had never published

any academic papers or conducted research or studies on the online disinhibition

effect, cybersexuality, fantasy, or role-play. Dr. Carr’s interview with Stahlman

lasted between one-and-a-half and three hours, and he did not meet with Stahlman

a second time. Dr. Carr did not speak to Stahlman’s wife, ex-wife, prior sexual

partners, or children. Dr. Carr did not review Stahlman’s National Guard service

records or other employment records.

      Dr. Carr further testified that Stahlman told him during their interview that

he had watched videos simulating sex between a father and minor daughter with

adults playing the parts. Dr. Carr asked Stahlman whether he ever had an interest

in children, and Stahlman “did not express an interest in children.” However,

Stahlman also told Carr that he had read and masturbated to erotic stories involving

adults and children, including stories on a website called Asstr.org, but Stahlman


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denied ever masturbating to pictures of children. Dr. Carr conducted a Static-99

test 2 of Stahlman and considered the results of a polygraph test in evaluating

Stahlman, but did not conduct any other psychosocial or sexual tests.

       On redirect, Dr. Carr testified that he learned, after his interview with

Stahlman, that no child pornography was found on Stahlman’s phone, but the

phone had evidence “of these daddy-daughter role-plays without any children, with

adults acting in that.” Dr. Carr opined that this was “consistent with [his]

findings.”

       The district court took the motion under advisement. On the first day of

trial, the district court granted the government’s motion to exclude Dr. Carr’s

testimony. The district court determined that Dr. Carr’s methodology was

unreliable, his testimony would not assist the jury, and his testimony would violate

Rule 704(b). The district court explained its decision as follows:

       In the Court’s view, Dr. Carr seeks to tell the jury that defendant was
       only role-playing and therefore lacked the requisite intent to commit
       the offense.

       To state the Court’s finding in the context of the Eleventh Circuit’s
       Daubert analysis:

       One, Dr. Carr is a qualified psychologist;

       Two, what little is known of Dr. Carr’s methodology is to this Court
       unreliable; and,

       2
        The Static-99 test is an assessment tool used for sex offender risk assessment in adult
male sex offenders.
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      Three, Dr. Carr’s testimony falls well short of assisting the trier of fact.

      Dr. Carr’s ultimate opinion invades the province of the jury as he seeks
      to substitute his judgment for the jury’s, in violation of Federal Rule of
      Evidence 704(b).

B.    Agent Hyre’s Testimony

      As the government’s first witness at trial, Agent Hyre testified that he had

been an FBI agent for 16 years and currently served as the coordinator for the

Violent Crimes Against Children Task Force, which investigates the sexual

exploitation of children. Agent Hyre received various types of training on how to

conduct such investigations, and that training included, among other things,

training on terminology used by sexual predators.

      During Agent Hyre’s testimony, Stahlman made a number of objections on

the ground that Agent Hyre, a lay witness, was improperly giving expert testimony.

Stahlman first objected when Agent Hyre, discussing Stahlman’s Craigslist ad,

stated: “To my experience, this ad would be flagged.” Initially, Stahlman objected

that this statement was “non-responsive,” and the district court overruled the

objection. Agent Hyre then continued his answer, but Stahlman objected again

when Agent Hyre said: “In other words, Craigslist users, when they see an ad that

they see to be illegal—[.]” At that point, Stahlman objected, citing Federal Rule of

Evidence 701, and stating “He’s not qualified as an expert on Craigslist postings.”



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      The district court called counsel up for a sidebar, and Stahlman’s counsel

reiterated, “I’m objecting to this as improper expert testimony.” Counsel for the

government responded that Agent Hyre’s testimony was appropriate lay witness

testimony and was “necessary to complete the story.” The district court then

engaged in this colloquy with the government:

      Court: Well, all I can do is apply my common sense here, and I know
             what Craigslist is. I know what their communications are, but
             his specific explanation of what these terms mean in the context
             of child solicitation, child whatever, I think that’s opinion
             testimony.

      Government Counsel (GC): Okay. So you’re saying that it’s excluded
            under 701?

      Court: No, I’m saying that you need an expert to testify to that.

      GC: Okay.

      Later, as Agent Hyre was testifying about his communications with

Stahlman, the government asked: “Now, in the context of this conversation, what

did you interpret, ‘I am selfish. I wouldn’t give mine up in exchange. Just getting

that out there,’ to mean?” Stahlman objected that the question called for an

improper opinion, and the government responded that “this is admissible under

Rule 701 as it’s in the context of the conversation.” The district court ruled:

“701(a), the Court’s finding is that this is rationally based, this witness’s

perception, this particular answer. The objection is overruled.”



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      Stahlman objected again when the government asked Agent Hyre what the

term “tickle fighting” meant. Initially, Stahlman objected on the ground that Agent

Hyre’s answer was non-responsive, and the district court overruled the objection.

Agent Hyre then finished his response, explaining that “tickle fighting” in this

context referred to when a sexual predator, in the course of tickling a child, “will

let their hands slip.” Stahlman objected again, this time on the basis of improper

opinion, citing Rule 701(c). The government agreed to “just move on,” and the

district court did not rule on the objection.

      Stahlman made his next objection when the government asked Agent Hyre,

“[I]n the context of this conversation, how did you interpret what he—when he

said, ‘qualify myself the opportunity,’” and Agent Hyre responded, “What does he

have to do to be able to meet my eleven-year-old.” Stahlman objected, stating:

“Again, I’m going to renew my previous objections to 701. (A) through (c) are

conjunction. They’re all required in order to be admitted, and I’m objecting as

improper expert testimony.” The district court ruled:

             Okay. Under 701, I hereby find that this testimony is rationally
      based on this witness’s perception; that it is helpful to clearly
      understanding the witness’s testimony or to determining a fact in issue;
      and based on the predicate that the government laid, there is specialized
      knowledge within the scope of this testimony.
             So based on that finding, and that finding is applicable
      retroactively, I’m going to allow this testimony. Your objection,
      though, is noted for the record.



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      Stahlman renewed his improper opinion objection again when the

government asked Agent Hyre: “Now, again, in the context of this conversation,

what did you interpret ‘trimmed downstairs’ to mean?” Stahlman’s counsel asked

to approach the bench, and the district court called both counsel to a sidebar, where

this colloquy ensued:

      Defense Counsel (DC): Your Honor, again, this is specialized
           knowledge and he hasn’t been disclosed as an expert to me, and
           I don’t know how this Court is finding that it’s—

      Court: Just let me ask you this.

      DC: Yes, Your Honor.

      Court: They laid a predicate on him of all the training he did, all the
            presentations he did, the fact that he’s been doing this for eight
            years, leading investigations, testifying in Court many times with
            regard to solicitation, child exploitation, and child pornography.
            Now, they haven’t asked that he be qualified as an expert, but,
            quite frankly, if they did, I would.
            But why doesn’t he have specialized knowledge in this area,
            based on the predicate that he laid?

      DC: If he did, Your Honor, I would have asked for a Daubert hearing
            and I would have filed my own motion in limine. I don’t think
            he’s an expert, Your Honor.

      Court: Well, every single trial he’s testified in these types of cases, he’s
            either been able to testify under 702 or qualified as an expert.
            So your position is he’s not an expert and, further, he has no
            specialized knowledge per 702?

      DC: Yes, Your Honor.

      Court: Okay.


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DC: And if Your Honor does find that he’s an expert, then I would
     move to strike him as they did not disclose him.

Court: I’m not making that finding. They haven’t requested it.
      But their position [is] that under 702, he meets the criteria and
      has specialized knowledge that would assist the jury in the
      context of that ruling. You disagree with that, correct?

DC: Yes, Your Honor.

Court: All right. What’s your position on that?

GC: Your Honor, under 701, he’s talking about the context of the
     conversation.
     The question was is he trimmed downstairs in the context of what
     they’re discussing. That’s both rationally based on his
     perception and helpful to understanding what—the fact at issue,
     which is what they were getting at.
     So I fail to understand how—why we’re here even.

DC: I guess I’m confused, because Your Honor is saying that this does
      require specialized knowledge, and now the government is
      saying that it doesn’t require specialized knowledge. I believe
      that it does, Your Honor.

Court: Well, there’s a mix of that. I will tell you that I don’t know that
      I would understand what “playing” means. But in the context of
      what he does, which I think they laid the predicate for, you
      picked an interesting hill to have a battle on, because I’m not the
      most hip person, but even I know what “trimmed downstairs”
      means, and I’m not an expert on this by any means.
      So if I ask the jurors one at a time, I’ll bet every one of them
      knows what that means. So I don’t know why that needs any
      expert experience at all.

DC: All of his opinion testimony I find to be improper. So can I have
     a standing objection?




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      Court: You can. But here’s where I’m having a problem. Look, if you
            want him to testify as to what he meant with what he wrote, that’s
            fine.
            If you want him to make—draw conclusions based on 701 based
            on what’s in there, that’s fine. But when you get more
            specialized than that, for example, what do you think he meant
            by what he wrote, then she’s got a point, because you’re having
            him interpret the other guy’s intent. And it’s a really fine line.

      GC: Okay.

      Court: All right. So it might just be easier to have him read all the
            e-mails. None of this is that difficult to understand.

       ....

      Court: All right. The objection is overruled.

      As Agent Hyre continued to testify, Stahlman objected once more to

improper opinion testimony when Agent Hyre stated, as to a particular email, “I

took that to mean he wasn’t a favorite of condoms.” The district court instructed

the government to have Agent Hyre just read the email.

      After the government’s direct examination, Stahlman moved for a mistrial

based on Agent Hyre’s improper opinion testimony. Stahlman argued that

(1) Agent Hyre was permitted to testify “to his opinion regarding what would

constitute terms that a sexual predator would use, his interpretation of what

[Stahlman] was saying, of what [Stahlman] meant,” and (2) the district court

“found that this was specialized knowledge,” but Agent Hyre was never disclosed

as an expert witness. The government responded that Agent Hyre’s testimony was


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permissible under either Rule 701 (as lay testimony) or Rule 702 (as expert

testimony). The government stressed that Agent Hyre’s testimony was based on

his perception of the communications, helpful to the jury, and circumscribed to the

context of the emails.

      The district court denied Stahlman’s motion for a mistrial. The district court

reasoned that the government laid a predicate for Agent Hyre’s knowledge and that

Stahlman was not “ambushed” by Hyre’s testimony regarding the emails.

C.    Stahlman’s First Motion for Judgment of Acquittal

      After Agent Hyre testified, the government presented two more witnesses, a

records custodian from Craigslist and another FBI agent. The government rested

its case, and Stahlman made his first motion for a judgment of acquittal.

      Stahlman’s counsel argued that there was insufficient evidence to support a

conviction because there was no evidence showing that he actually intended to

engage in sexual activity with a minor, as opposed to merely engaging in fantasy

role-playing with an adult. Stahlman contended that all of the evidence was

consistent with fantasy role-playing, and there was no objective evidence (such as

incriminating items in his car or child pornography on his phone) to show that his

actual intent was to have sex with a minor.




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      The district court denied Stahlman’s motion. The district court observed

that, at that point, there was no evidence to support Stahlman’s fantasy role-

playing theory and the evidence was sufficient to proceed further.

D.    Stahlman’s Defense

      At the outset of his defense, Stahlman testified. Stahlman had two nieces,

whose lives he was very involved in as they grew up. He had three children of his

own—two sons from a previous marriage and one stepson with his current wife.

      Since around September 2014, Stahlman had used Craigslist to seek fantasy

relationships with other adults. Through his Craigslist activities, Stahlman had

traveled to meet ten adults. Stahlman explained that, in his Craigslist ads, he

adopts the “fantasy portrayal of a man named ‘Sam.’” Stahlman stated that

“Sam’s” age would vary from ad to ad and that “Sam” “has fantasies” and

“portrays fantasies with other adults.”

      Stahlman testified that, in September 2016, he posted an ad similar to the

November 2016 ad Agent Hyre ultimately responded to. Stahlman later deleted

that September 2016 ad because he “wasn’t getting any traction,” and then posted

the November 2016 ad, which “modified the language a little bit” and had a photo

attached. Stahlman was motivated to post the November 2016 ad because he

recently broke up with his long-term girlfriend and “had been searching for another

person to have sex with,” but “wasn’t having any . . . luck.” Stahlman stated that


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he “posted [his] normal post, which is about sexting,” but did not get any

responses, so he moved on to his “second thing,” which “is to go into like a fantasy

portrayal.”

      Stahlman elaborated: “I often go to fantasies, and I had done a massage

fantasy. I had done a soldier fantasy. I had done a fantasy about . . . like you have

no information about the person, you just meet and have sex.” As to the particular

daddy-daughter fantasy in the November 2016 ad, Stahlman stated: “So when I

was doing research on what type of fantasies are out there, I came across daddy-

daughter fantasies, and I found out that some women have daddy fetishes. So I

thought, you know, it might be an avenue that I could go down.”

      Stahlman explained that his sexual communications, whether via texting,

Kik, or email, were “definitely in the realm of fantasy” and “outside [his] regular

life.” Stahlman described these sexual communications prior to meeting someone

as a sort of interview process to make sure that the other person “fit[s] the part”

and can convincingly act out the fantasy.

      Regarding Agent Hyre’s response to his November 2016 ad, Stahlman

testified that he “believed [it] was a response to [his] Craigslist ad requesting a

sexual fantasy.” Stahlman stated that, “[i]n fantasy, there’s in-character and out-

of-character comments,” and the goal of fantasy role-playing is to “stay in

character as much as possible.” Thus, when Stahlman received Agent Hyre’s


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response to his ad, his “first instinct was this person was in character.” Based on

Agent Hyre’s response, Stahlman believed he would be acting out his fantasy with

“a straight man and a woman who’s going to be portraying an eleven-year-old

daughter.”

      As he reviewed the emails between Agent Hyre and himself, Stahlman

testified that the majority of the messages were “in character” on his part and, he

believed, “in character” on Agent Hyre’s part as well. In other words, Stahlman

indicated that the majority of his responses were meant to further the fantasy

scenario he and Agent Hyre were discussing. Stahlman acknowledged, however,

that some messages, such as when he told Agent Hyre he was busy at work or

when Agent Hyre told him he had to attend a meeting, were out of character.

Stahlman explained that he did not ask for confirmation that Agent Hyre was also

engaging in fantasy role-playing when Agent Hyre first responded to the ad

because he inferred that someone responding to his “ad about a fantasy” was

engaging in that same fantasy. Stahlman stated that it “would have been breaking

the atmosphere” to ask for confirmation that Agent Hyre was also engaging in

fantasy.

      Stahlman testified that he had never had sex with a minor or had sexual

thoughts about children. In communicating with Agent Hyre, Stahlman never

believed he was talking to an actual pedophile with a real minor daughter. Rather,


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he believed Agent Hyre was acting as an intermediary in the fantasy for his adult

wife or girlfriend. When Agent Hyre sent him the picture of his supposed 11-year-

old, Stahlman “didn’t believe the photo was real” and assumed the couple he

believed he was talking to “just uploaded a photo that didn’t really exist” or “found

a photo like I did online.”

      Stahlman explained that when he told Agent Hyre in December 2016 to

“[g]o ahead and delete [him],” it was because his schedule was busy and he

“wasn’t willing to do the back and forth” of emailing if he was not going to be able

to actually meet the couple he believed he was talking to. Stahlman also stated that

some people on Craigslist “just do endless e-mails and continue forever and it

never really pans out to anything, and I wasn’t interested in that either.” When

Agent Hyre reached back out to him 45 days later, in late-January 2017, Stahlman

believed he was “trying to re-engage the fantasy.” Stahlman explained that his

repeated questions to Hyre about condoms were an “in character” way to ask if the

adult woman he believed he would be engaging with “was on some form of birth

control.” Stahlman explained that this was “very important to [him]” because

“impregnating an adult [was] completely out of the question” given his personal

circumstances.

      When he went to meet with Agent Hyre, Stahlman “believed that there was a

chance that if somebody was eavesdropping on the[ir] conversation,” it was


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possible he could be caught up in a sting operation. Stahlman assumed, however,

that if that happened, it would be easy to demonstrate that “there was no actual

eleven-year-old girl . . . in the scenario at all,” and it was just fantasy. Stahlman

described his Teenage Mutant Ninja Turtles t-shirt as “vintage” and “not the

version that’s on TV today that children watch.”

      Stahlman also presented the expert testimony of Richard Conner, a computer

forensics consultant. Conner had conducted forensic examinations in cases

involving alleged sexual misconduct, including approximately 240 child

pornography cases. Conner testified that the female in the picture Stahlman posted

with his Craigslist ad was classified as “age difficult,” meaning he could not tell if

the picture was of an adult or a child. Conner also forensically examined the

contents of Stahlman’s cell phone. Conner examined approximately 87 videos and

more than 2,000 still images on Stahlman’s phone and did not find any images or

video of children in the nude or depicted in a sexually explicit manner. Conner

also did not find any evidence of deleted files, encryption software, or software

that could be used to clean up deleted files. Conner also did not find any child

pornography on Stahlman’s phone.

E.    Stahlman’s Second Motion for Judgment of Acquittal

      After Conner’s testimony, the defense rested. Stahlman renewed his motion

for a judgment of acquittal. Stahlman contended that, because he is presumed


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innocent until proven otherwise, his “ad was presumed non-criminal until the

government proved that it was not.” Stahlman maintained that the ad “sought

fantasy,” and his own unrebutted testimony demonstrated that “he showed up

because he was expecting an adult and he was operating this entire e-mail and Kik

dialogue as a role-play.”

      The government responded that the totality of the evidence, viewed in the

light most favorable to the government, demonstrated that Stahlman did attempt to

entice a minor to engage in sexual activity and took a substantial step toward doing

so by showing up at the Gander Mountain parking lot. The government

emphasized that Stahlman repeatedly indicated in the emails that he was interested

in meeting the fictional 11-year-old, and the details of his conversation with Agent

Hyre demonstrated that Stahlman “wanted to groom the child into easing her into a

sexually exploitive situation.”

      The district court again denied Stahlman’s motion for judgment of acquittal.

The district court found that there were competing theories of the case, and it was

for the jury to decide which was true. The jury disbelieved Stahlman and

convicted him of attempting to entice a minor to engage in sexual activity, in

violation of 18 U.S.C. § 2422(b).

F.    Sentencing




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       The presentence investigation report (“PSR”) calculated Stahlman’s total

offense level as a 40, consisting of: (1) a base offense level of 28, pursuant to

U.S.S.G. § 2G1.3(a)(3); (2) a two-level increase under U.S.S.G. § 2G1.3(b)(3)

because his offense involved the use of a computer; (3) an eight-level increase

under U.S.S.G. § 2G1.3(b)(5) because the offense involved a minor under the age

of 12; and (4) a two-level increase for obstruction of justice, pursuant to U.S.S.G.

§ 3C1.1, based on Stahlman’s perjured testimony at trial. As to perjury, the PSR

recounted that: (1) Stahlman “informed the jury he has never had sexual thoughts

about children”; but (2) during his proffered examination, outside the presence of

the jury, he “acknowledged masturbating to sexually explicit stories engaging

minors posted on the ASSTR.org website.” 3 Stahlman’s total offense level of 40

and criminal history category of I resulted in an advisory guidelines range of 292

to 365 months’ imprisonment. His § 2422 conviction carried a mandatory

minimum sentence of 10 years. The probation officer recommended a low-end

sentence of 292-months’ imprisonment.



       3
         After testifying before the jury, Stahlman proffered testimony, outside the presence of
the jury, regarding the absence of child pornography on his phone. Stahlman testified that he had
87 videos and over 2,000 still images on his phone, and none of those videos or images depicted
children in the nude or in sexually explicit positions.
        On cross-examination during this proffer, Stahlman admitted that his phone did contain
an email with a link to ASSTR.org, which is “a collection of erotic fantasies and erotic stories
uploaded by anonymous authors.” Stahlman further acknowledged that authors post sexually
explicit stories about minors on ASSTR.org, including stories about children aged 10 to 12.
Stahlman stated that he had read, and masturbated to, three such stories.
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      Stahlman filed a written objection to the obstruction of justice enhancement.

Stahlman submitted that the mere fact that his trial testimony did not coincide with

Agent Hyre’s was not evidence of obstruction—Stahlman “simply exercised his

constitutional right to trial as well as to testify.” Stahlman asserted that the

probation officer’s and the government’s belief that he lied was insufficient to

warrant the obstruction enhancement and, in any event, he had not lied. Stahlman

argued that “when asked questions by the government during the proffered cross

examination regarding the asstr.org stories, those stories were based on fantasy,”

whereas “[t]he question asked during direct examination in front of the jury,” about

his sexual attraction to children, “was based on reality.” Because the questions

were different, Stahlman contended, he did not lie. Stahlman additionally pointed

out that the jury did not hear his testimony during the proffer, and thus his answer

did not bear on the verdict.

      The probation officer responded that Stahlman’s testimony about

masturbating to sexually explicit stories involving minors was contradictory to his

earlier testimony that he never had sexual thoughts about children. The probation

officer therefore maintained that the obstruction enhancement was appropriate.

      At the sentencing hearing, Stahlman did not offer any additional argument

regarding his objection to the obstruction enhancement. The district court

overruled Stahlman’s objection, stating that “[a]s to the controverted . . . guideline


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applications, the Court adopts the position of the Probation Office as stated in the

[PSR] addendum.” The district court determined that Stahlman’s total offense

level was 40, his criminal history category was I, and his advisory guidelines range

was 292 to 365 months’ imprisonment.

      Stahlman argued for a mandatory-minimum, below-guidelines sentence of

10 years, based on, among other things, his lack of criminal history, his years of

military service, the fact that he is an engaged and involved father to his sons, and

the fact that he will experience collateral consequences from having to register as a

sex offender. The government requested a within-guidelines sentence,

emphasizing various factors including the seriousness of Stahlman’s offense, the

explicit nature of his communications with Agent Hyre, and the fact that he

traveled to meet the fictional 11-year-old.

      In pronouncing Stahlman’s sentence, the district court remarked, “[b]luntly,

Mr. Stahlman, your position on what happened here was implausible.” The district

court elaborated:

             If you were indeed only involved in role-playing and had no
      intention to do this, there is simply no plausible answer for why you
      would drive from Seminole County, Florida, to Orange County,
      Florida, to meet in that parking lot, dressed the way you were, in order
      to do anything but meet with that child.
             Your position went from implausible to incredible for me. The
      jury didn’t believe you and, frankly, I don’t believe you. . . .
             I don’t blame you for taking the position that you have. I don’t
      blame you for defending yourself. You’re certainly never going to be
      penalized in any courtroom, and you shouldn’t be, for exercising your
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       right to a trial. But you can be held accountable for what you say at
       trial, and what you said at trial simply wasn’t true.

The district court then sentenced Stahlman to 292 months’ imprisonment.

Stahlman objected that the sentence was procedurally and substantively

unreasonable. On September 28, 2017, Stahlman filed his first notice of appeal,

which was docketed as case number 17-14387.

G.     Stahlman’s Post-Trial Motion for New Trial

       While his appeal was pending, Stahlman filed a “Motion for New Trial,

Request for an Indicative Ruling, and Prayer for an Evidentiary Hearing,” under

Federal Rule of Criminal Procedure 33 and Federal Rule of Appellate Procedure

12.1, in the district court. In his motion, Stahlman explained that on November 2,

2017, after his May 2017 trial and September 2017 sentencing, the government

disclosed for the first time 4 that Agent Hyre was sanctioned by the FBI in August

2013 for conducting undercover child exploitation investigations using his home

computer.

       Specifically, the November 2 disclosure advised that the FBI “issued

administrative disciplinary action against [Agent Hyre]” in August 2013, in the

form of a seven-day suspension without pay, after finding “that SA Hyre violated



       4
          This disclosure was made in a different case in the Middle District of Florida, but as that
defendant and Stahlman were both represented by the Federal Public Defender’s Office in that
district, Stahlman’s counsel also learned of the disclosure.
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FBI policy by using a home computer to conduct undercover child sexual

exploitation investigations.” The disclosure further stated that, because of Agent

Hyre’s unauthorized use of his personal computer during an undercover operation,

Homeland Security Investigations (“HSI”), “not knowing that SA Hyre was acting

in an undercover capacity, investigated SA Hyre’s online identity.” Upon learning

who Agent Hyre was, HSI provided the information to the FBI for further action.

      During the subsequent FBI investigation, Agent Hyre admitted to using his

home computer for investigative purposes on several occasions but stated that he

was unaware doing so was in violation of FBI policy. Although the standard

penalty for such a violation is a five-day suspension, the FBI found that

“aggravation was appropriate because SA Hyre’s actions caused him to be the

subject of a child pornography investigation by another federal agency,” and he

“acknowledged engaging in similar behavior on several other occasions.” Agent

Hyre contested the finding that he had violated FBI policy, as well as the severity

of the sanction, but the FBI upheld his seven-day suspension.

      Stahlman’s post-trial motion argued that Agent Hyre’s prior discipline

constituted “newly discovered evidence” of either a Brady5 violation or a Federal

Rule of Criminal Procedure 16 violation, and the suppression of this evidence

substantially prejudiced his rights to a fair trial, to present his theory of defense,


      5
          Brady v. Maryland, 373 U.S. 83, 83 S. Ct. 1194 (1963).
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and to attack the elements of the charged offense. As to his Brady claim, Stahlman

contended that Agent Hyre’s prior discipline constituted impeachment evidence

that was favorable to him. Stahlman further asserted that, had this evidence been

timely disclosed, there was a reasonable probability the outcome of his trial would

have been different. Stahlman emphasized that his case “really boiled down to a

credibility determination” between himself and Agent Hyre, and having

information about Agent Hyre’s prior discipline would have “played a material and

substantial factor” in how Stahlman prepared his defense.

      As to his discovery violation claim, Stahlman submitted that the

government’s failure to disclose Agent Hyre’s prior discipline was an egregious

violation of Criminal Rule 16. Stahlman acknowledged that, to obtain a new trial

on a non-Brady, newly discovered evidence claim, the evidence cannot be “merely

impeaching.” Stahlman maintained, however, that Agent Hyre’s prior discipline

was “so much more” than just impeachment evidence, as having that information

would have affected Stahlman’s entire trial strategy.

      Stahlman acknowledged that, because his appeal in Case No. 17-14387 was

then pending, the district court lacked jurisdiction to grant his motion for new trial.

Stahlman therefore requested that the district court enter an indicative ruling

certifying that the motion should be granted, which would allow this Court to




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consider a motion to remand jurisdiction to the district court to hold an evidentiary

hearing and address the merits of his new trial motion. 6

       In response, the government argued that Stahlman’s Brady claim failed

because: (1) he did not coherently articulate how evidence of Agent Hyre’s prior

discipline would have changed the outcome of the trial; (2) he failed to show how

Hyre’s prior discipline would be admissible; (3) Hyre’s misconduct “did not

involve any finding of dishonesty or untruthfulness,” making it inadmissible as

evidence bearing on credibility under Federal Rule of Evidence 608(b); (4) Hyre’s

discipline would also be inadmissible under Rules 403 and 404(b); (5) other

circuits have found a law enforcement policy violation does not constitute Brady

material; and (6) in any event, the evidence against Stahlman was “overwhelming,”

making it unlikely that evidence of Hyre’s prior discipline would have altered the

jury’s verdict.

       As to Stahlman’s discovery violation claim, the government argued that

Agent Hyre’s prior discipline was merely impeachment evidence and that

Stahlman failed to show it was material or would have produced a different result




       6
        After filing his motion for new trial in the district court, Stahlman filed a motion with
this Court requesting that Case No. 17-14387 be stayed pending the district court’s ruling on his
new trial motion. This Court granted Stahlman’s motion for a stay until the district court ruled
on Stahlman’s post-trial motion.
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at trial. Lastly, the government asserted that an evidentiary hearing was not

required to resolve Stahlman’s motion.

      In a June 2018 order, the district court denied Stahlman’s new trial motion.

The district court acknowledged that Appellate Rule 12.1 supplies the rule for a

district court’s consideration of a Criminal Rule 33 motion based on newly

discovered evidence while an appeal is pending. However, the district court went

on to recite the legal standards governing motions for new trial “based on the

weight of the evidence.” The district court then stated:

      Defendant elected to testify at trial. The written communications
      between Special Agent Hyre and Defendant were introduced as
      evidence. The substance of those communications were not at issue.
      Defendant told the jury that he was simply role-playing and that his
      statements were in no way a sincere attempt to engage in sexual activity
      with a child. This was not, as Defendant continues to argue, a
      credibility determination between the testimony of Special Agent Hyre
      and Defendant. Rather, Defendant urged the jury to rely on his
      interpretation of the electronic communications instead of their own
      common sense interpretation. The jury declined to do so.

The district court then denied Stahlman’s Criminal Rule 33 motion and stated: “In

the Court’s view, the Motion does not raise a substantial issue.”

      Stahlman filed a new notice of appeal from the denial of his post-trial

motion, which was docketed as case number 18-12866 in this Court. We

consolidated that appeal with Stahlman’s earlier appeal in Case No. 17-14387.

      With this background, we turn to Stahlman’s issues on appeal.



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                         III. EVIDENTIARY RULINGS

      Stahlman raises two claims of evidentiary error: (1) improper exclusion of

Dr. Carr’s expert testimony; and (2) improper admission of Agent Hyre’s lay

testimony on matters that were the subject of expert testimony. We first review the

rules governing expert testimony and then address each claim.

A.    Applicable Federal Rules of Evidence

      Under the Federal Rules of Evidence, opinion testimony by witnesses is

divided into two categories: lay testimony and expert testimony. See Fed. R. Evid.

701 & 702. If a witness is testifying as a lay witness, and not as an expert, that

witness may only testify to an opinion that is:

      (a) rationally based on the witness’s perception;

      (b) helpful to clearly understanding the witness’s testimony or to
      determining a fact in issue; and

      (c) not based on scientific, technical, or other specialized knowledge
      within the scope of Rule 702.

Fed. R. Evid. 701.

      By contrast, “[a] witness who is qualified as an expert by knowledge, skill,

experience, training, or education” may give opinion testimony if:

      (a) 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;

      (b) the testimony is based on sufficient facts or data;


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      (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.

Fed. R. Evid. 702. If the government intends to present a witness as an expert in a

criminal trial, the government must disclose that witness as an expert prior to trial

and provide a written summary of the expected testimony. See Fed. R. Crim. P.

16(a)(1)(G); United States v. Hamaker, 455 F.3d 1316, 1331 (11th Cir. 2006).

      In determining whether to admit expert testimony under Rule 702, district

courts must consider if: (1) the expert is qualified to give competent testimony

about the matters he intends to address; (2) the methodology the expert employed

to reach his conclusions is sufficiently reliable under Daubert 7; and (3) the

testimony will assist the trier of fact, through the application of scientific,

technical, or other specialized expertise, to understand the evidence or determine a

fact in issue. City of Tuscaloosa v. Harcros Chems., Inc., 158 F.3d 548, 562 (11th

Cir. 1998).

      In Daubert, the Supreme Court explained that a district court faced with a

proffer of expert testimony must assess whether the reasoning or methodology

underlying the testimony is scientifically valid and can properly be applied to the

facts in issue. Daubert, 509 U.S. at 592-93, 113 S. Ct. at 2796. Many factors bear



      7
          Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 113 S. Ct. 2786 (1993).
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on that inquiry, including: (1) whether the theory or technique has been or can be

tested; (2) whether the theory or technique has been subjected to peer review and

publication; (3) the known or potential error rate; and (4) whether the theory or

technique is widely accepted. Id. at 593-94, 113 S. Ct. at 2796-97. The Supreme

Court emphasized that the Rule 702 inquiry is “a flexible one,” the ultimate goal of

which is to determine the evidentiary relevance and reliability of the proposed

expert testimony. Id. at 594-95, 113 S. Ct. at 2797.

      Even if an expert’s proposed testimony satisfies Rule 702 and Daubert, the

testimony also must comply with other limitations contained in the Rules of

Evidence. Of relevance here, Rule 704(b) provides:

      In a criminal case, an expert witness must not state an opinion about
      whether the defendant did or did not have a mental state or condition
      that constitutes an element of the crime charged or of a defense. Those
      matters are for the trier of fact alone.

Fed. R. Evid. 704(b). In other words, an expert may not opine on the defendant’s

intent. See United States v. Augustin, 661 F.3d 1105, 1123 (11th Cir. 2011).

However, an expert may, consistent with Rule 704(b), give testimony “that

supports an obvious inference with respect to the defendant’s state of mind if that

testimony does not actually state an opinion on [the] ultimate issue, and instead

leaves this inference for the jury to draw.” Id. (internal quotations and alteration

omitted).



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B.     Dr. Carr’s Testimony and Rule 704(b)

       The district court excluded Dr. Carr’s testimony for two reasons. First, it

concluded that Dr. Carr’s testimony was inadmissible under Rule 702 because his

methodology was unreliable, and his testimony would not assist the trier of fact.

Second, it determined that Dr. Carr’s testimony would violate Rule 704(b). 8

Because we agree with the district court that Dr. Carr’s testimony was inadmissible

under Rule 704(b), we do not address its separate conclusion that his testimony

was also inadmissible under Rule 702.

       Here, Stahlman sought to present Dr. Carr’s opinions that “[t]here [was]

insufficient behavioral evidence to conclude that Mr. Stahlman intended to have

real sex with a minor, rather than act out a fantasy involving adults,” and that

“[t]he clinical evidence suggests that Mr. Stahlman intended to act out a fantasy,

rather than have sexual contact with a minor.” (emphasis added). These statements

plainly run afoul of Rule 704(b)’s directive that an expert not opine on whether a

criminal defendant had or did not have the requisite mental state to commit the



       8
          “We review for abuse of discretion the district court’s decisions regarding the
admissibility of expert testimony and the reliability of an expert opinion.” United States v.
Frazier, 387 F.3d 1244, 1258 (11th Cir. 2004) (en banc). “Indeed, the deference that is the
hallmark of abuse-of-discretion review requires that we not reverse an evidentiary decision of a
district court unless the ruling is manifestly erroneous.” Id. (internal quotations and citation
omitted). “Thus, it is by now axiomatic that a district court enjoys considerable leeway in
making these determinations.” Id. (internal quotations omitted). “[W]e must affirm unless we
find that the district court has made a clear error of judgment, or has applied the wrong legal
standard.” Id. at 1259.
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charged crime. See Fed. R. Evid. 704(b). In testifying that the clinical and

behavioral evidence showed Stahlman intended to act out a fantasy with adults,

rather than engage in sex with a minor, Dr. Carr would be doing more than

providing testimony that supports an inference as to intent—he would, in effect, be

telling the jury Stahlman did not intend to induce a minor to engage in sexual

activity. See 18 U.S.C. § 2422(b); Augustin, 661 F.3d at 1123; see also United

States v. Hofus, 598 F.3d 1171, 1180 (9th Cir. 2010) (“To say that Hofus meant

the texting only as fantasy is simply another way of saying he did not really intend

to entice or persuade the young girls, which is precisely the question for the jury.”).

      In arguing to the contrary, Stahlman cites the D.C. Circuit’s decision in

United States v. Hite, 769 F.3d 1154, 1168-1170 (D.C. Cir. 2014), a § 2422

prosecution in which the D.C. Circuit reversed the district court’s exclusion of the

defendant’s expert witness. In Hite, the defendant sought to present the expert

testimony of Dr. Frederick Berlin on, inter alia, (1) the difference between an

actual desire to engage in sex with a minor and mere fantasy or role-playing, and

(2) his diagnosis that the defendant Hite did not suffer from any psychiatric

condition associated with, or that would predispose a person to, a desire to have

sexual contact with minors. Id. at 1168. Importantly, the district court in Hite did

not exclude the expert’s proffered testimony under Rule 704(b). See id. Rather, it

excluded Dr. Berlin’s testimony because it found the testimony was not properly


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disclosed under Federal Rule of Criminal Procedure 16 and had little probative

value. Id.

      On appeal, the D.C. Circuit not only rejected the district court’s Rule 16

analysis, but also concluded that “[b]ecause the District Court determined that

Hite’s sexual interest in children was relevant to the question of whether he had the

requisite intent with respect to 18 U.S.C. § 2422(b), Hite should have been

permitted to introduce [Dr. Berlin’s testimony] so that he could seek to

demonstrate to the jury that he did not possess such an interest.” Id. at 1169. The

D.C. Circuit further noted that Dr. Berlin’s proposed general testimony concerning

fantasy and role-playing could “shed light on what may be an unfamiliar topic to

most jurors: sexual fantasy involving children, particularly the kind that unfolds in

the virtual realm of the Internet.” Id. at 1170. The D.C. Circuit then stated that

“Dr. Berlin may not testify that Hite lacked the requisite intent, see Fed. R. Evid.

704(b),” but that “expert testimony that generally explains the world of sexual

fantasy on the Internet is permissible.” Id.

      Hite is distinguishable from Stahlman’s case because the proposed testimony

in Hite was materially different from, and did not go as far as, Dr. Carr’s proffered

testimony here. In Hite, the defendant sought to have his expert testify about

(1) the difference, generally speaking, between real-life attraction to children and

online fantasy and role-playing, and (2) the fact that the defendant Hite had not


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been diagnosed with any psychiatric condition that was associated with a sexual

attraction to children. Id. at 1168. While that testimony might support an

inference that the defendant Hite lacked the requisite intent to induce a minor to

engage in sexual activity, see Augustin, 661 F.3d at 1123, neither of those

statements directly opines on the defendant’s intent.

       Here, by contrast, Dr. Carr’s proposed testimony went beyond general

testimony about online fantasies and Stahlman’s psychiatric diagnosis. Rather,

Dr. Carr directly opined that Stahlman intended to act out a fantasy and did not

intend to have sex with a minor. Under Rule 704(b), this is a bridge too far.9 We

therefore conclude that the district court did not abuse its discretion in excluding

Dr. Carr’s testimony.

C.     Agent Hyre’s Testimony

       Stahlman contends that the district court erred in allowing Agent Hyre to

offer lay opinions regarding: (1) the age of the girl in the picture Stahlman posted


       9
         We note that Stahlman does not argue on appeal that the district court should have more
narrowly circumscribed its ruling, excluding only those opinions that it found violated Rule
704(b), while allowing Dr. Carr to provide more general testimony akin to that at issue in Hite.
See also United States v. Joseph, 542 F.3d 13, 21-22 (2d Cir. 2008) (urging the district court to
“give a more thorough consideration” on retrial to the defendant’s proposed expert testimony
“about role-playing in the context of sexually explicit conversations on the Internet”), abrogated
in part on other grounds as recognized in United States v. Ferguson, 676 F.3d 260, 276 n.14 (2d
Cir. 2011); United States v. Gladish, 536 F.3d 646, 650-51 (7th Cir. 2008) (concluding district
court should have allowed expert to testify regarding the defendant’s use of the internet “to
gratify his sexual desires” and preference for “emotional and physical distance” in interpersonal
relationships, making it “unlikely, given the defendant’s psychology, that he would act on his
intent”). Accordingly, we express no opinion as to whether a more limited version of Dr. Carr’s
testimony might have been permissible.
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with his Craigslist ad; (2) what Craigslist is used for; (3) whether Stahlman’s ad

would be “flagged”; (4) what Stahlman meant in the ad; (5) Hyre’s interpretation

of the email communications between Hyre and Stahlman; and (6) what he thought

Stahlman meant in those communications. Stahlman asserts that all of this

testimony was based on specialized knowledge and could not be offered as lay

testimony. Further, the government did not disclose or present Agent Hyre as an

expert witness.10

       The district court appears to have based its rulings on Agent Hyre’s

testimony on a misunderstanding of the rules concerning lay and expert witnesses.

Despite allowing the government to present Agent Hyre as a lay witness, the

district court specifically found that “there is specialized knowledge within the

scope of this testimony.” But Rule 701(c), addressing lay opinion testimony,

makes quite clear that a lay witness’s opinions must “not [be] based on scientific,

technical, or other specialized knowledge within the scope of Rule 702.”

Fed. R. Evid. 701(c) (emphasis added); see also Fed. R. Evid. 702 (addressing

expert testimony).



       10
          We review a district court’s ruling regarding the admissibility of lay opinion testimony
under Rule 701 for a clear abuse of discretion. United States v. Jayyousi, 657 F.3d 1085, 1102
(11th Cir. 2011). Errors in admitting opinion testimony as lay testimony are subject to harmless
error review. See United States v. Sarras, 575 F.3d 1191, 1217 (11th Cir. 2009). Additionally,
we will not reverse a conviction based on a Rule 16 expert disclosure violation unless the
violation prejudiced the defendant’s substantial rights. See Hamaker, 455 F.3d at 1332; United
States v. Tinoco, 304 F.3d 1088, 1119-20 (11th Cir. 2002).
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       When a district court bases an evidentiary ruling on an erroneous view of the

law, that “constitutes an abuse of discretion per se.” United States v. Henderson,

409 F.3d 1293, 1297 (11th Cir. 2005). However, errors in admitting opinion

testimony as lay testimony are subject to harmless error review. See United States

v. Sarras, 575 F.3d 1191, 1217 (11th Cir. 2009). In other words, we will not

reverse a conviction based on an erroneous evidentiary ruling unless the error had a

substantial influence on the outcome of the case or leaves us in grave doubt as to

whether the error affected the outcome. Henderson, 409 F.3d at 1300.

       Here, we conclude that the district court’s error in applying the rules

regarding lay and expert witnesses to Agent Hyre’s testimony was harmless. First,

some of Agent Hyre’s testimony Stahlman challenges was undoubtedly proper lay

opinion testimony under Rule 701. For example, Agent Hyre’s estimate as to the

age of the girl in the picture Stahlman posted required no specialized knowledge—

any lay witness may properly estimate the age of a person in a photograph based

solely on their perception. See Rule 701(a); cf. also United States v. Smith, 459

F.3d 1276, 1297 n.18 (11th Cir. 2006) (indicating that an officer’s testimony that

certain photographs depicted “very, very young girls” was not plainly based on

specialized knowledge, as opposed to a mere lay opinion).11


       11
         We note that courts in this Circuit have at times admitted expert testimony concerning
the age of a child depicted in a videotape. See United States v. Anderton, 136 F.3d 747, 750
(11th Cir. 1998) (discussing competing expert testimony presented at trial regarding age of
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       Similarly, Agent Hyre’s testimony that the “Personals, Casual Encounters”

section of Craigslist, where Stahlman posted his ad, was “used as kind of like a

hookup site” where “people go on to find other persons to meet up with and

generally have sex with,” was within the realm of proper lay testimony. Any

person looking at that portion of the Craigslist website could, without having any

specialized knowledge, perceive that its purpose was to facilitate casual sexual

encounters. Furthermore, even some of Agent Hyre’s interpretations of

Stahlman’s emails—such as his understanding of what word Stahlman meant to

use when there were typographical errors in the emails—were based solely on his

perceptions of the conversation and not on any specialized knowledge from his

experience as a law enforcement officer.

       Agent Hyre’s other testimony—regarding what posts would be “flagged” on

Craigslist and interpreting what Stahlman meant in his ad and in his email

communications—is perhaps closer to the line, but nevertheless falls within the

permissible bounds of lay testimony under this Court’s precedent. This Court has

held that a law enforcement agent may properly testify as a lay witness about the

meaning of code words used in intercepted calls based on what the agent learned




children in a video). In Anderton, however, the Court did not address whether such age estimate
testimony must come from an expert or requires specialized knowledge. See id. In other words,
it certainly may be permissible for an expert to testify regarding a person’s estimated age, but
that does not necessarily mean that only an expert can give such testimony.
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during his five-year terrorism investigation. See United States v. Jayyousi, 657

F.3d 1085, 1104 (11th Cir. 2011). Similarly, this Court has concluded that law

enforcement officers may offer lay testimony about the meaning of coded terms in

a narcotics case based on both “their perceptions [in the instant case] and on their

[past] experience as police officers,” albeit under an earlier version of Rule 701

that did not contain the current version’s restriction that testimony not be based on

specialized knowledge. See United States v. Novaton, 271 F.3d 968, 1008-09

(11th Cir. 2001); see also Tampa Bay Shipbuilding & Repair Co. v. Cedar

Shipping Co., 320 F.3d 1213, 1223 & n.17 (11th Cir. 2003) (approving lay witness

testimony that was “based upon their particularized knowledge garnered from

years of experience within the field” and “find[ing] no basis to determine that

Novaton . . . require[d] a different finding after Rule 701’s amendment”).

      Here, Agent Hyre’s testimony about flagged posts on Craigslist and his

interpretations of Stahlman’s statements in his ad and in his email communications

were based on Agent Hyre’s perceptions as a participant in his conversations with

Stahlman in this case and informed by his years of experience investigating child

exploitation and child pornography crimes. As explained above, this Court has

held that testimony of that nature is a proper subject for a lay witness. See

Jayyousi, 657 F.3d at 1104; Tampa Bay Shipbuilding, 320 F.3d at 1223; Novaton,

271 F.3d at 1008-09. Further, in the circumstances here, Agent Hyre in this case


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was testifying to give his side of the story as to what his messages meant. The

district court did not clearly abuse its discretion in permitting Agent Hyre to testify

as a lay witness. See Jayyousi, 657 F.3d at 1102.

      Moreover, even if some of Agent Hyre’s testimony veered into the realm of

specialized knowledge that ought to have been disclosed and presented as expert

testimony, any error in admitting that testimony as lay testimony was harmless.

See Sarras, 575 F.3d at 1217. First, Stahlman has not demonstrated that the

government’s failure to disclose Agent Hyre as an expert prior to trial under

Criminal Rule 16 prejudiced his substantial rights. See Hamaker, 455 F.3d at

1332; United States v. Tinoco, 304 F.3d 1088, 1119-20 (11th Cir. 2002). The

government identified Agent Hyre as a witness before trial, and Stahlman was

“aware of his role in the investigation,” had copies of all the email and Kik

messages between himself and Hyre, and knew that Hyre’s testimony would be

based on his communications with Stahlman. See Hamaker, 455 F.3d at 1332.

Furthermore, the district court explicitly stated at trial that, had Agent Hyre been

offered as an expert, the district court would have admitted him as such. So we

know that any motion in limine Stahlman might have raised to exclude Agent

Hyre’s expert testimony would likely have failed. Finally, as explained below,

ample evidence supported Stahlman’s conviction, and Stahlman has not shown that




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the outcome of the trial would have been different absent Agent Hyre’s allegedly

improper lay testimony. See Sarras, 575 F.3d at 1217.

       In sum, we conclude that the district court did not reversibly err in allowing

Agent Hyre to testify as a lay witness or in denying Stahlman’s motion for a

mistrial on that basis.

               IV. MOTIONS FOR JUDGMENT OF ACQUITTAL

       Stahlman next argues that the district court erred in denying his motions for

a judgment of acquittal because the evidence was insufficient to prove his intent or,

relatedly, that he took a substantial step toward carrying out that intent. 12 In

essence, Stahlman submits that the trial evidence established two competing

hypotheses of his intent—either, as Stahlman testified, he was seeking a fantasy

with an adult posing as a minor, or, as Agent Hyre testified, he intended to engage

in sex with an actual minor. According to Stahlman, proof of his guilt beyond a

reasonable doubt required that the government exclude every reasonable

hypothesis but that of guilt, and the government failed to do so because there was a

reasonable innocent explanation for his actions.



       12
          We review de novo the district court’s denial of a motion for judgment of acquittal on
sufficiency of the evidence grounds. United States v. Keen, 676 F.3d 981, 994 (11th Cir. 2012).
In doing so, we review the trial evidence in the light most favorable to the government, drawing
all reasonable factual inferences in favor of the verdict. United States v. Henderson, 893 F.3d
1338, 1348 (11th Cir. 2018). If there is “any reasonable construction of the evidence [that]
would have allowed the jury to find the defendant guilty beyond a reasonable doubt,” we will not
overturn the jury’s verdict. Id. (internal quotation omitted).
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      Here, the statute of conviction, § 2422(b), proscribes knowing attempts to

induce or entice a minor to engage in sexual activity, stating:

      Whoever, using the mail or any facility or means of interstate or foreign
      commerce, . . . knowingly persuades, induces, entices, or coerces any
      individual who has not attained the age of 18 years, to engage in
      prostitution or any sexual activity for which any person can be charged
      with a criminal offense, or attempts to do so, shall be fined under this
      title and imprisoned not less than 10 years or for life.

18 U.S.C. § 2422(b). To prove that a defendant violated § 2422(b) by attempting

to induce a minor to engage in sexual activity, the government must show that the

defendant (1) had the specific intent to induce a minor to engage in sexual activity,

and (2) took a substantial step toward the commission of that offense. United

States v. Lee, 603 F.3d 904, 913-14 (11th Cir. 2010); United States v. Yost, 479

F.3d 815, 819 (11th Cir. 2007).

      A substantial step is an “objective act[]” that “mark[s the defendant’s]

conduct as criminal such that his acts as a whole strongly corroborate the required

culpability.” United States v. Murrell, 368 F.3d 1283, 1288 (11th Cir. 2004). This

Court has held that a defendant may be convicted under § 2422(b) even if he

attempted to exploit only a fictitious minor and communicated only with an adult

intermediary. See Lee, 603 F.3d at 912-13; see also Murrell, 368 F.3d at 1286-87.

      Ample evidence supports Stahlman’s conviction for attempting to entice a

minor to engage in sexual activity. The trial evidence showed that Stahlman

engaged in a monthslong conversation with a man he believed to be the parent of
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an 11-year-old daughter, during which he discussed in graphic detail plans to meet

and engage in sexual activity with the daughter. This conversation began with

Stahlman’s own Craigslist post seeking a “daddy/daughter fantasy” with a “young

‘looking’ girl.” Stahlman was the first to broach the possibility of engaging in

sexual activity with Agent Hyre’s fictional 11-year-old, stating that he would not

violate his own daughter, but “would play with someone else’s,” and telling Agent

Hyre “I just envisioned licking your daughter’s pussy as she slept and you filming

it.”

       As the conversation progressed, Stahlman’s responses demonstrated his

strong sexual interest in the 11-year-old daughter, including his explicit

descriptions of the types of sex acts he wanted to engage in with the girl.

Stahlman’s messages likewise evinced his intent to induce the daughter, through

her father, to engage in sexual activity. For example, Stahlman asked Agent Hyre

what he would have to do to “qualify” for the opportunity to meet the daughter,

asked questions about what types of sex acts Agent Hyre would or would not

consent to, and asked Agent Hyre what the daughter would enjoy.

       And Stahlman’s interest remained strong throughout the conversation—even

when Stahlman’s scheduling conflicts prevented him from carrying out the first

planned meeting in November 2016, Stahlman told Agent Hyre he had not changed

his mind and was still interested in sex with the daughter if he could find the time.


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Once the January 2017 meeting was set, Stahlman reiterated how much he was

looking forward to meeting the daughter, and Stahlman took a substantial step

toward doing so when he drove from his home in Longwood (wearing a child-

friendly Ninja Turtles t-shirt) to meet Agent Hyre in Lake Mary.

      Stahlman protests that there is an innocent explanation for all of this

conduct—namely, that the entire thing was a big misunderstanding, as he believed

he was conversing with an adult couple as part of a fantasy role-playing scenario,

and not with the father of an actual 11-year-old girl. The problem for Stahlman is

that the jury was not required to accept this innocent explanation. Indeed, because

Stahlman testified in his own defense at trial, the jury was free to (and, based on

their verdict, clearly did) disbelieve his testimony and consider it as substantive

evidence of his guilt. See United States v. Bacon, 598 F.3d 772, 776 (11th Cir.

2010).

      Contrary to Stahlman’s contention, this Court is not required on appeal to

rule out every hypothesis of innocence. Rather, in reviewing the sufficiency of the

evidence supporting a jury’s guilty verdict, we must review the evidence in the

light most favorable to the government and draw all reasonable factual inferences

in favor of the verdict. United States v. Henderson, 893 F.3d 1338, 1348 (11th Cir.

2018). And if there is “any reasonable construction of the evidence [that] would

have allowed the jury to find the defendant guilty beyond a reasonable doubt,” we


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will not overturn the jury’s verdict. Id. (internal quotations omitted); see also

United States v. Peters, 403 F.3d 1263, 1268 (11th Cir. 2005) (stating that the “jury

is free to choose among reasonable constructions of the evidence,” and the

evidence need not “exclude every reasonable hypothesis of innocence” (internal

quotations omitted)). Here, there is such a reasonable construction of the evidence.

The jury reasonably could have concluded (and clearly did conclude) beyond a

reasonable doubt that, despite Stahlman’s testimony to the contrary, Stahlman

meant what he said in his communications with Agent Hyre and traveled to the

Gander Mountain in Lake Mary for the purpose of carrying out the sexual acts he

had described with the 11-year-old girl.

       Because sufficient evidence supported Stahlman’s § 2422(b) conviction, the

district court did not err in denying his motions for judgment of acquittal.13

               V. OBSTRUCTION OF JUSTICE ENHANCEMENT

       Stahlman next asserts that the district court erroneously applied a two-level

obstruction of justice enhancement, rendering his 292-month sentence procedurally




       13
          Stahlman also contends that the cumulative effect of the trial errors requires reversal of
his conviction. Under the cumulative error doctrine, an aggregation of otherwise nonreversible
errors can warrant reversal where the combined effect of the errors denied the defendant his
constitutional right to a fair trial. See United States v. Mosquera, 886 F.3d 1032, 1052 (11th Cir.
2018). As explained above, the district court committed no trial error, and thus Stahlman’s
cumulative error claim fails. See United States v. King, 751 F.3d 1268, 1277-78 (11th Cir. 2014)
(stating “where there is no error or only a single error, there can be no cumulative error” (internal
quotations omitted)).

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and substantively unreasonable.14 Stahlman contends that (1) the district court

failed to make any particularized factual findings regarding his alleged perjury, and

(2) this Court lacks a meaningful basis for appellate review. 15

       Under § 3C1.1 of the Sentencing Guidelines, a two-level enhancement

applies if the defendant obstructed justice. U.S.S.G. § 3C1.1. Specifically,

§ 3C1.1 provides:

       If (1) the defendant willfully obstructed or impeded, or attempted to
       obstruct or impede, the administration of justice with respect to the
       investigation, prosecution, or sentencing of the instant offense of
       conviction, and (2) the obstructive conduct related to (A) the
       defendant’s offense of conviction and any relevant conduct; or (B) a
       closely related offense, increase the offense level by 2 levels.

Id. The commentary to § 3C1.1 further provides that a defendant qualifies for the

obstruction enhancement if he commits perjury. Id. § 3C1.1, comment. n.4(B).

       The Supreme Court has defined perjury in this context as “false testimony

concerning a material matter with the willful intent to provide false testimony,

rather than as a result of confusion, mistake, or faulty memory.” United States v.



       14
          We review a district court’s factual findings supporting an obstruction of justice
enhancement for clear error and its application of the guidelines to those facts de novo. United
States v. Perkins, 787 F.3d 1329, 1341 (11th Cir. 2015). In doing so, we “accord great deference
to the district court’s credibility determinations,” and also “give due deference to the district
court’s application of the guidelines to the facts.” United States v. Singh, 291 F.3d 756, 763
(11th Cir. 2002) (internal quotations omitted).
       15
         Contrary to the government’s contention, we conclude that Stahlman properly
preserved his challenge to the obstruction enhancement by including it in his objections to the
PSR and by objecting to his sentence’s procedural reasonableness after the district court
pronounced his sentence.
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Dunnigan, 507 U.S. 87, 94, 113 S. Ct. 1111, 1116 (1993). A “material” matter

under § 3C1.1 is “evidence, fact, statement, or information that, if believed, would

tend to influence or affect the issue under determination.” U.S.S.G. § 3C1.1,

comment. n.6.

      In Dunnigan, the Supreme Court explained that “not every accused who

testifies at trial and is convicted will incur an enhanced sentence under § 3C1.1 for

committing perjury,” noting that not all testimony that is inaccurate is perjurious.

See Dunnigan, 507 U.S. at 95, 113 S. Ct. at 1117. The Supreme Court therefore

explained that when a defendant objects to an obstruction enhancement resulting

from his trial testimony, “a district court must review the evidence and make

independent findings necessary to establish a willful impediment to or obstruction

of justice, or an attempt to do the same.” Id. The Supreme Court further stated

that, “[w]hen doing so, it is preferable for a district court to address each element

of the alleged perjury in a separate and clear finding.” Id. However, the Supreme

Court also stated that a district court’s determination that the obstruction

enhancement applies is sufficient as long as “the court makes a finding of an

obstruction of, or impediment to, justice that encompasses all of the factual

predicates for a finding of perjury.” Id.; see also United States v. Singh, 291 F.3d

756, 763 (11th Cir. 2002) (“[A] general finding that an enhancement is warranted




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suffices if it encompasses all of the factual predicates necessary for a perjury

finding.” (internal quotations omitted)).

      Here, as an initial matter, we disagree with Stahlman’s contention that there

is no meaningful basis for appellate review. Certainly, Stahlman is correct that the

district court did not, at the sentencing hearing, specifically “address each element

of the alleged perjury in a separate and clear finding.” Dunnigan, 507 U.S. at 95,

113 S. Ct. at 1117. But the district court did explicitly “adopt[] the position of the

Probation Office as stated in the [PSR] addendum,” which lays out the factual

basis for applying the obstruction enhancement. Specifically, the PSR Addendum

explains:

      The defendant, under oath, made materially false statements.
      According to the jury trial transcript, defense counsel asked Stahlman,
      “Have you ever had sexual thoughts about children?” Stahlman
      responded, “No, I have not.” However, during the government’s
      proffered cross-examination, the government questioned Stahlman
      about an author on a website known as asstr.org. Stahlman explained
      that asstr is a collection of erotic fantasies and erotic stories uploaded
      by anonymous authors. When asked what people do on asstr.org, he
      said, “They post sexually explicit stories generally engaging minors.”
      He then acknowledged having read several of these sexually explicit
      stories. The government then asked, “Mr. Stahlman, do you masturbate
      to those stories?” Stahlman responded, “Yes.” Based on this
      information, it appears the defendant was not honest to the jury as this
      latter statement contradicts his statement that he has never had sexual
      thoughts about children.

      Additionally, in pronouncing its sentence, the district court clearly indicated

that it did not find Stahlman’s trial testimony credible and that it was holding


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Stahlman “accountable for what [he said] at trial” because “what [he said] at trial

simply wasn’t true.” While it may have been “preferable” for the district court to

provide a more detailed discussion of its reasons for applying the obstruction

enhancement at sentencing, we are not left without any meaningful basis for

review here. See Dunnigan, 507 U.S. at 95, 113 S. Ct. at 1117; Singh, 291 F.3d at

763.

       We also discern no clear error in the factual findings underlying the

obstruction enhancement or any error in the district court’s application of the

guidelines to those facts. The district court’s findings (as outlined in the PSR

Addendum) support a finding of perjury. To show perjury, “(1) the testimony must

be under oath or affirmation; (2) the testimony must be false; (3) the testimony

must be material; and (4) the testimony must be given with the willful intent to

provide false testimony and not as a result of mistake, confusion, or faulty

memory.” United States v. Ellisor, 522 F.3d 1255, 1277 n.34 (11th Cir. 2008)

(internal quotations omitted). Here, Stahlman’s testimony that he never had sexual

thoughts about children (1) was made under oath at trial and (2) undoubtedly was

material to whether Stahlman actually intended to engage in sexual activity with an

11-year-old. See id.; U.S.S.G. § 3C1.1, comment. n.6.

       Stahlman disputes that his testimony about his lack of sexual interest in

children was false and thus, likewise, disputes that it was given with the willful


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intent to provide false testimony. But given Stahlman’s later proffered testimony

that he had masturbated to erotic stories about adults engaging in sex with children,

it was not clearly erroneous for the district court to find that Stahlman’s earlier

testimony before the jury was not truthful. Stahlman asserts that the Asstr.org

stories were mere fantasies that do not reflect his real-life desires. Importantly

though, these were not stories describing adults engaged in fantasy role-playing, in

which one adult was portraying a minor, but rather were stories describing sexual

encounters between adults and children. In other words, the Asstr.org stories may

have been fantasies, but they are fantasies about children, not adults acting as

children, and Stahlman’s interest in those stories belies his statement that he never

had sexual thoughts about children. In this context, too, we “accord great

deference to the district court’s credibility determinations,” and here the district

court explicitly found Stahlman’s testimony to be “implausible” and “incredible.”

Singh, 291 F.3d at 763 (internal quotations omitted).

      In short, the district court did not err in finding Stahlman had perjured

himself at trial and, having so found, properly applied the two-level obstruction of

justice enhancement under § 3C1.1. See U.S.S.G. § 3C1.1 & comment. n.4(B);

Dunnigan, 507 U.S. at 94-95, 113 S. Ct. at 1116-17. We therefore affirm

Stahlman’s 292-month sentence.




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                           VI. MOTION FOR NEW TRIAL

       Stahlman’s final argument is that the district court erred in denying his

“Motion for New Trial, Request for an Indicative Ruling, and Prayer for an

Evidentiary Hearing.” 16 Specifically, Stahlman frames the issue as both a Brady

claim and a Rule 16 discovery violation.

       We agree with the government’s concession that, because Stahlman’s new

trial motion was based on the non-disclosure of Agent Hyre’s prior discipline, the

district court erred by using the “against the weight of the evidence” standard. But

we also agree with the government that Stahlman’s claims fail under the correct

legal standards and that any error was harmless.

A.     Brady Claim

       To establish a Brady violation, the defendant must show: (1) the government

possessed evidence that was favorable to him; (2) he did not possess the evidence

and could not have obtained it with reasonable diligence; (3) the prosecution

suppressed the favorable evidence; and (4) if the evidence had been disclosed,

there is a reasonable probability that the outcome of his trial would have been

different. United States v. Vallejo, 297 F.3d 1154, 1164 (11th Cir. 2002).




       16
         We review for an abuse of discretion the denial of a motion for new trial (1) based on
newly discovered evidence, United States v. Barsoum, 763 F.3d 1321, 1341 (11th Cir. 2014),
and (2) based on an alleged Brady violation, United States v. Naranjo, 634 F.3d 1198, 1206 (11th
Cir. 2011).
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Evidence is “favorable” under Brady if it is exculpatory or impeaching. See

United States v. Naranjo, 634 F.3d 1198, 1212 (11th Cir. 2011). “A reasonable

probability is a probability sufficient to undermine confidence in the outcome.”

United States v. Hano, 922 F.3d 1272, 1292 (11th Cir. 2019) (internal quotations

omitted).

      Stahlman contends that Agent Hyre’s prior discipline constitutes favorable

evidence under Brady because it is impeachment evidence that could have

undermined the jury’s confidence in Agent Hyre’s testimony. The government

disagrees, arguing, inter alia, that: (1) the November 2, 2017 notice indicates that

Agent Hyre admitted his policy violation during the disciplinary investigation, and

“[t]here were no allegations or findings of lack of candor or untruthfulness on his

part”; (2) that Stahlman failed to establish any inconsistency in Agent Hyre’s trial

testimony and his assertions to the FBI investigators; and (3) Stahlman failed to

show evidence of the suspension was material under Brady.

      We need not delve into those matters because, even assuming Agent Hyre’s

prior discipline does carry some impeachment value, we see no reasonable

probability that, had this evidence been disclosed, the outcome of Stahlman’s trial

would have been different. Vallejo, 297 F.3d at 1164. As we explained above in

discussing Stahlman’s motions for judgment of acquittal, ample evidence—

primarily in the form of Stahlman’s own emails to Agent Hyre graphically


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describing the sex acts he wished to perform on the 11-year-old daughter—

supported Stahlman’s conviction in this case. None of the content of Stahlman’s

online communications with Agent Hyre was disputed. The only contested issue

was whether Stahlman intended to entice a minor or whether he, as he testified,

believed he was only acting out a sexual role-playing fantatsy with consenting

adults. We simply fail to see how evidence of Agent Hyre’s prior discipline,

which was wholly unrelated to this case and had but little, if any, bearing on the

credibility of his testimony, would have tipped the balance in this case so

significantly as to undermine our confidence in the jury’s guilty verdict. Hano,

922 F.3d at 1292. The district court’s error in failing to properly analyze

Stahlman’s Brady claim was therefore harmless. See United States v. Hernandez,

433 F.3d 1328, 1335-37 (11th Cir. 2005) (concluding that the district court’s error

in employing the wrong legal standard to evaluate a motion for new trial was

harmless).

B.    Rule 16 Violation

      Under Federal Rule of Criminal Procedure 16, the government must disclose

to the defendant any evidence that “is material to preparing the defense.”

Fed. R. Crim. P. 16(a)(1)(E)(i). This Court will not reverse a conviction based on

a Rule 16 discovery violation unless the defendant demonstrates that the violation

prejudiced his substantial rights. United States v. Chastain, 198 F.3d 1338, 1348


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(11th Cir. 1999); United States v. Camargo-Vergara, 57 F.3d 993, 998 (11th Cir.

1995).

      To obtain a new trial based on newly discovered evidence, a defendant must

show that: (1) the evidence was discovered after trial; (2) his failure to discover the

evidence was not due to a lack of diligence; (3) the evidence is not merely

cumulative or impeaching; (4) the evidence is material; and (5) the evidence is

such that a new trial would probably produce a different result. United States v.

Barsoum, 763 F.3d 1321, 1341 (11th Cir. 2014). This Court has repeatedly stated

that motions for new trial based on newly discovered evidence are “highly

disfavored” and should be granted only with “great caution.” See United States v.

Scrushy, 721 F.3d 1288, 1304 (11th Cir. 2013); United States v. Campa, 459 F.3d

1121, 1151 (11th Cir. 2006); United States v. Jernigan, 341 F.3d 1273, 1287 (11th

Cir. 2003).

      Stahlman’s Rule 16 violation/newly discovered evidence claim fails for

much the same reasons as his Brady claim. As explained above, Agent Hyre’s

prior discipline is, at best, merely impeaching evidence, as it has no bearing on

Stahlman’s guilt or innocence in this case. See Barsoum, 763 F.3d at 1341. And,

as also explained above, given the ample evidence supporting Stahlman’s guilt,

evidence of Agent Hyre’s prior discipline would not probably produce a different

outcome. See id. In short, we see no reason here to throw “great caution” to the


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wind and take the “highly disfavored” step of granting Stahlman a new trial on this

basis. See Scrushy, 721 F.3d at 1304. Again, the district court’s error in applying

the wrong standard to Stahlman’s claim was harmless.

      Given our conclusions regarding the merits of Stahlman’s motion for new

trial, we also conclude that the district court did not err in declining to conduct

discovery, hold an evidentiary hearing, or hold oral argument on Stahlman’s

motion. See Jernigan, 341 F.3d at 1289 (indicating that a district court does not err

in denying an evidentiary hearing on a motion for new trial where the defendant’s

claim was properly denied).

                                VII. CONCLUSION

      For the foregoing reasons, we affirm Stahlman’s § 2422 child enticement

conviction and 292-month sentence.

      AFFIRMED.




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