In the 

United States Court of Appeals 

For the Seventh Circuit ____________________

No. 19‐2853

UNITED STATES OF AMERICA,

Plaintiff‐Appellee,

v.

LANCE A. WEHRLE,

Defendant‐Appellant.

____________________

Appeal from the United States District Court for the

Southern District of Illinois.

No. 17‐CR‐30074‐NJR — Nancy J. Rosenstengel, Chief Judge.

____________________

ARGUED SEPTEMBER 25, 2020 — DECIDED JANUARY 15, 2021

____________________

Before RIPPLE, BRENNAN, and ST. EVE, Circuit Judges.

BRENNAN, Circuit Judge. After detecting an internet proto‐

col address downloading child pornography, police executed

a warrant to search Lance Wehrle’s home. They seized hard

drives and digital devices that contained over one million

photos and videos of child pornography. The search also

turned up lascivious photos taken in his home depicting the

seven‐year‐old nephew of Wehrle’s friend.  
2 No. 19‐2853

Wehrle was indicted for producing and possessing child

pornography. Following a bench trial he was convicted and

sentenced to 40 years’ imprisonment. On appeal Wehrle chal‐

lenges various district court rulings underlying his conviction

and sentence. We affirm in all respects.  

I

In March 2017, Jerseyville, Illinois, Police Officer Amanda

Wimmersberg detected an IP address requesting child por‐

nography using a peer‐to‐peer file‐sharing network called

Freenet. As a member of the Federal Bureau of Investigation’s

Violent Crimes Against Children Task Force and Internet

Crimes Against Children Task Force, she was certified to in‐

vestigate on Freenet and had previously conducted more than

40 similar investigations. Wimmersberg determined that the

IP address belonged to Wehrle, and she and other agents exe‐

cuted a search warrant on his residence.  

During the search the agents found a photo album in

Wehrle’s bedroom. In the album they discovered a photo‐

graph depicting A.E. lying on a blanket with his penis ex‐

posed. The background of the photograph matched the items

they found in Wehrle’s living room—a red blanket, a circular

TV stand, and a fish tank—indicating that the picture was

taken inside his home. The agents seized external hard drives,

flash cards, and other digital devices. A preliminary forensic

review of the hard drives revealed additional pornographic

images of A.E. These images depicted Wehrle performing oral

sex on A.E., Wehrle holding a cigarette lighter next to A.E.’s

genitals, and A.E. performing lewd acts on a sex toy. Wim‐

mersberg reviewed the devices and found over one million

images and videos of child pornography, including more than

50 additional images of A.E. In an interview with police the
No. 19‐2853 3

same day as the search, Wehrle acknowledged he had down‐

loaded child pornography using Freenet.  

A federal grand jury indicted Wehrle on two counts of pro‐

ducing child pornography and one count of possessing child

pornography.1 The case went to a bench trial at which

Wimmersberg testified about her investigation and the foren‐

sic examination process. She described her professional back‐

ground and experience, as well as the methods she employed

to extract the data from Wehrle’s digital devices.2 She also de‐

tailed the hardware and software used to maintain the integ‐

rity of the original data.  

The district court viewed approximately 70 images and

videos, 28 of which featured A.E. Wehrle attempted to dis‐

qualify Wimmersberg as an expert witness, but the district

court “found her to be credible and that her credentials and

qualifications for the investigation in this case were not in any

way suggestive that the evidence was in any way not properly

obtained or there was any problem with the investigation.”

The district court found Wehrle guilty on each of the indict‐

ment’s three counts and sentenced him to a below‐guidelines

sentence of 40 years’ imprisonment: 30 years on each of the

production counts to be served concurrently, and 10 years on

the possession count to be served consecutively.  

1 The district court had jurisdiction over the criminal case pursuant to

18 U.S.C. § 3231.

2 The devices from which the offending files were extracted included

hard drives, USB drives, and memory cards, but no cell phones. R. 65.
4 No. 19‐2853

II

Wehrle raises four challenges on appeal: (1) whether the

district court abused its discretion by failing to qualify Wim‐

mersberg as an expert witness; (2) whether the admission of

trade inscriptions found on the seized devices violated the

rule against hearsay and the Sixth Amendment Confrontation

Clause; (3) whether 18 U.S.C. § 2251(a), which criminalizes the

production of child pornography, violates the Commerce

Clause; and (4) whether the district court’s sentencing deci‐

sion was substantively unreasonable.3

A

First is Wehrle’s claim that Wimmersberg should have

been qualified as an expert witness. We review a district

court’s evidentiary rulings for abuse of discretion. See Turub‐

chuk v. S. Ill. Asphalt Co., Inc., 958 F.3d 541, 548 (7th Cir. 2020).

Even if a district court abused its discretion, “[w]e will not re‐

verse if the error is harmless in light of the trial record as a

whole.” Viramontes v. City of Chicago, 840 F.3d 423, 430 (7th Cir.

2016). When a party fails to preserve an objection at trial, we

review for plain error. See FED. R. CRIM. P. 52(b); Puckett  v.

United States, 556 U.S. 129, 135 (2009).  

Wehrle argues the district court abused its discretion by

failing to qualify Wimmersberg as an expert witness when her

detailed discussion of the technical aspects of her investiga‐

tion deviated into opinion testimony under Federal Rule of

Evidence 702. When Wimmersberg began discussing the im‐

age‐extracting process, Wehrle’s counsel objected based on

3 This court has jurisdiction pursuant to 28 U.S.C. §§ 41 and 1291, and

jurisdiction to review Wehrle’s sentence pursuant to 18 U.S.C. § 3742.
No. 19‐2853 5

“foundation” and “Rule 702.” He repeated the same objection

throughout hertestimony by referencing his “earlier objection

based upon the processing.” We conclude that these repeated

invocations sufficiently preserved this objection to the tech‐

nical aspects of Wimmersberg’s testimony, so we review the

district court’s ruling on this evidence for abuse of discretion.

Expert testimony generally involves technical concepts be‐

yond ordinary understanding. See FED. R. EVID. 702. “[A]n of‐

ficer testifies as an expert when he brings ‘the wealth of his

experience as [an] officer to bear on those observations and

ma[kes] connections for the jury based on that specialized

knowledge.’” United States v. Gaytan, 649 F.3d 573, 582 (7th

Cir. 2011) (some alterations in original) (quoting United States

v. Oriedo, 498 F.3d 593, 603 (7th Cir. 2007)). A forensic‐exami‐

nation process falls within Rule 702’s ambit if it involves “spe‐

cialized knowledge [that] will assist the trier of fact to under‐

stand the evidence or to determine a fact in issue.” FED. R.

EVID. 702; see also Daubert v. Merrell Dow Pharm., Inc., 509 U.S.

579, 589–91 (1993).

The forensic‐examination process here implicated Rule

702 because Wimmersberg testified to technical concepts be‐

yond ordinary knowledge. During her direct examination,

she was asked, “How do you go about conducting a forensic

examination of a device?” She first explained the use of a

“write blocker,” a tool that permits access to data while pro‐

tecting the integrity of the seized device. She then described

the use of data‐extraction software. She also described the re‐

liability and safeguards in the software that prevent any alter‐

ation of the original data, and she discussed other technical

concepts such as hashes (which convert one value to another
6 No. 19‐2853

and can establish identity) and metadata (data which gives

information about other data).  

We recognize that not all testimony about the use of “tech‐

nical” equipment will implicate Rule 702. Some uses are com‐

monplace today. But even if a lay person may understand an

officer’s testimony about one of these concepts in isolation, an

explanation of how they work together to preserve infor‐

mation and the integrity of the data crosses into Rule 702

territory. So we conclude Wimmersberg’s testimony here con‐

cerning technical aspects of a forensic examination constitutes

“specialized knowledge” under Rule 702.4 Admitting her spe‐

cialized knowledge without formally qualifying her as an ex‐

pert witness was an abuse of discretion.

Although the district court abused its discretion, any error

associated with the admission of this testimony was harmless.

See FED. R. CRIM. P. 52(a) (“Any error ... that does not affect

substantial rights must be disregarded.”). An error is harm‐

less if it “do[es] not have an effect on the outcome because the

case against the defendant is so overwhelming absent the er‐

roneously admitted evidence.” United States v. Quiroz, 874

F.3d 562, 571 (7th Cir. 2017); see also United States v. Brown, 871

F.3d 532, 536 (7th Cir. 2017) (“[A] new trial is appropriate only

if the average juror would have found the government’s case

significantly less persuasive had the wrongly excluded evi‐

dence been admitted.”). The evidence of Wehrle’s guilt at the

bench trial was overwhelming. He confessed to police about

abusing A.E. and downloading child pornography. At least

one of the photographs depicted Wehrle performing oral sex

on A.E., and the pornographic nature of the photos Wehrle

4 R. 122 at 66–68.
No. 19‐2853 7

produced and possessed was not disputed at trial. Even if the

district court’s admission of Wimmersberg’s testimony about

the forensic examination technology is deemed improper, the

government could have presented another witness to offerthe

same explanations about the data‐extraction software. Be‐

cause the outcome would have been the same, the error was

harmless.

While we conclude that Wimmersberg’s detailed discus‐

sion of the technical aspects of her investigation crossed over

into expert testimony, her characterization of the images as

“child pornography” did not. We review this question for

plain error because Wehrle’s counsel failed to specifically

raise this objection at trial.5 Under plain‐error review, a de‐

fendant must show (1) an “error or defect,” (2) that is “clear

or obvious,” (3) affecting his “substantial rights,” (4) that “se‐

riously affect[s] the fairness, integrity or public reputation of

judicial proceedings.” Puckett, 556 U.S. at 135 (internal quota‐

tion marks omitted).

Wimmersberg answered “yes” to the prosecutor’s ques‐

tion asking whether the seized devices contained “child por‐

nography.” Wehrle argues that characterization was not

merely descriptive, but the phrase instead constituted an im‐

permissible legal conclusion.  

Wehrle’s challenge here falls short. We have held that ex‐

pert testimony is unnecessary if “the fact that the unidentified

5 Wehrle claims he objected to Wimmersberg’s characterization of the

images and videos as “child pornography,” which the government dis‐

putes. We read the transcript as Wehrle objecting to the officer’s discus‐

sion of the technical aspects of the forensic examination process, but not

the use of the phrase “child pornography.” R. 122.
8 No. 19‐2853

subject is a child will be obvious from appearance.” United

States v. Dewitt, 943 F.3d 1092, 1096 (7th Cir. 2019); see also

United States v. Lacey, 569 F.3d 319, 325 (7th Cir. 2009)

(“[E]xpert evidence is not required to prove the reality of chil‐

dren portrayed in pornographic images.”). Wimmersberg’s

characterization of the images as “child pornography” was

properly admitted as fact testimony because it was an ordi‐

nary and accepted way to describe what she had observed. See

Dewitt, 943 F.3d at 1096. Wehrle’s images and videos depicted

children, and they involved the display of genitalia and sex‐

ual acts. So the district court did not err when it admitted

Wimmersberg’s “child pornography” characterization.

B

Wehrle’s second challenge to his conviction concerns the

admission of trade inscriptions on his seized equipment. He

contends those inscriptions constituted inadmissible hearsay

and violated his Sixth Amendment right to confront the evi‐

dence against him.  

Hearsay. Hearsay is defined as an out‐of‐court statement

offered to prove the truth of the matter asserted. See FED. R.

EVID. 801(c)(1). Hearsay evidence is generally inadmissible

unless an exception applies. See FED.R. EVID. 803. Even if hear‐

say evidence does not fall under any of the enumerated

exceptions, a court may admit the otherwise inadmissible ev‐

idence under Rule 807’s residual exception. To satisfy the

residual exception, a proponent of hearsay evidence must

establish five elements: (1) circumstantial guarantees of trust‐

worthiness; (2) materiality; (3) probative value; (4) the inter‐

ests of justice; and (5) notice. See FED. R. EVID. 807; see also

United States v. Moore, 824 F.3d 620, 622 (7th Cir. 2016). Trial

courts have broad discretion in admitting evidence under
No. 19‐2853 9

Rule 807. See id. We review Wehrle’s hearsay claim for abuse

of discretion because he objected on that ground at trial. See

United States v. Turner, 836 F.3d 849, 857 (7th Cir. 2016).

On appeal, the government argues the trade inscriptions

found on Wehrle’s devices, even if hearsay, are admissible un‐

der Rule 807’s residual exception. Here the trade inscriptions

“Made in China” and “Product of China” were affixed to

Wehrle’s camera, flash cards, and hard drives. The govern‐

ment introduced the evidence to establish that Wehrle

produced and possessed child pornography with materials

transported using channels of interstate or foreign commerce.

The district court did not abuse its discretion in admitting

the trade inscriptions. We will reverse only if “no reasonable

person could take the view adopted by the trial court.” United

States v. Vargas, 552 F.3d 550, 554 (7th Cir. 2008). We have

stated “[t]he purpose of Rule 807 is to make sure that reliable,

material hearsay evidence is admitted, regardless of whether

it fits neatly into one of the exceptions enumerated in the

Rules of Evidence.” Moore, 824 F.3d at 624. Trade inscriptions

are self‐authenticating, meaning they “require no extrinsic ev‐

idence of authenticity in order to be admitted.” FED. R. EVID.

902.

While self‐authentication alone does not qualify a trade in‐

scription as an exception to the hearsay rule, trade inscrip‐

tions exhibit a high level of trustworthiness, satisfying Rule

807. Federal regulations require trade inscriptions on prod‐

ucts imported from abroad and prohibit false or misleading

designations of origin. See 19 U.S.C. § 1304(a); 15 U.S.C.

§ 1125(a). There is also little incentive for a company to man‐

ufacture a product in the U.S. and then deceptively affix a

“Made in China” trade inscription. Other circuits agree that
10 No. 19‐2853

trade inscriptions have sufficient indicia of reliability to sat‐

isfy the residual exception. See, e.g., United States v. Boles, 914

F.3d 95, 109 (2d Cir. 2019); United States v. Burdulis, 753 F.3d

255, 263–64 (1st Cir. 2014).

Confrontation Clause. Wehrle also argues the admission of

the trade inscriptions violated his rights under the Sixth

Amendment’s Confrontation Clause. Because he raises this

objection for the first time on appeal, we review for plain er‐

ror. FED. R. CRIM. P. 52(b). See United States v. Barber, 937 F.3d

965, 967 (7th Cir. 2019).

The Confrontation Clause prohibits the “admission of tes‐

timonial statements of a witness who did not appear at trial

unless he was unavailable to testify, and the defendant had

had a prior opportunity for cross‐examination.” Crawford v.

Washington, 541 U.S. 36, 53–54 (2004). This right applies only

to testimonial evidence. See Giles v. California, 554 U.S. 353, 376

(2008). Testimonial evidence includes “formal statements to

government officers, or formalized testimonial materials such

as affidavits, depositions, and the like, that are destined to be

used in judicial proceedings.” United States v. Brown, 822 F.3d

966, 974 (7th Cir. 2016). Business records, however, are gener‐

ally nontestimonial because “they are not made for the

purpose of later prosecution.” Id. Cf. Melendez‐Diaz v.

Massachusetts, 557 U.S. 305, 321 (2009) (noting that documents

created for use at trial do not qualify as business records).

The trade inscriptions at issue are nontestimonial. The in‐

scriptions denoting an item’s foreign origin are not created in

preparation for a future judicial proceeding. Rather, they are

created to comply with federal regulations requiring labels of

place of origin for imported products. Because trade
No. 19‐2853 11

inscriptions are nontestimonial, there is no Confrontation

Clause issue here, and the district court did not err in admit‐

ting them.  

C

Next Wehrle contends that 18 U.S.C. § 2251(a), which

criminalizes the production of child pornography, violates

the Commerce Clause. Because he failed to raise this chal‐

lenge at trial, we review for plain error. See United States v.

Williams, 410 F.3d 397, 400 (7th Cir. 2005).

The Commerce Clause enables Congress to regulate and

protect the use of the channels of commerce, instrumentalities

of interstate commerce, and those activities having a substan‐

tial relation to interstate commerce. See United States v. Lopez,

514 U.S. 549, 558–59 (1995). This authority extends to “purely

local activities that are part of an economic ‘class of activities’

that have a substantial effect on interstate commerce.”

Gonzalez v. Raich, 545 U.S. 1, 17 (2005). We have held that

§ 2251(a) is constitutional when evaluating whether the stat‐

ute was a permissible exercise of Congress’s Commerce

Clause power “to prevent the spread of injurious or immoral

uses. ... and also to protect those channels from the immoral

impact of child pornography.” United States v. Schaffner, 258

F.3d 675, 680 (7th Cir. 2001) (citation omitted).

In § 2251(a) Congress has validly exercised its power un‐

der the Commerce Clause. Congress has proper authority to

regulate this field because possession and production of child

pornography substantially affect interstate commerce. In

United States v. Blum, we highlighted that “the manufacture

and possession of any child pornography itself feeds the mar‐

ket and increases demand for it.” 534 F.3d 608, 612 (7th Cir.
12 No. 19‐2853

2008), abrogated on other grounds by United States v. Vizcarra, 668

F.3d 516 (7th Cir. 2012); see also Ashcroft v. Free Speech Coalition,

535 U.S. 234, 249 (2002) (recognizing the interstate market for

child pornography). Wehrle possessed and produced child

pornography using devices that had been mailed, shipped, or

transported using channels of interstate commerce. That is an

adequate hook for Congress to exercise its Commerce Clause

power. The district court did not commit any error when it

rejected Wehrle’s Commerce Clause challenge.

D

That leaves us with Wehrle’s challenge to the substantive

reasonableness of his sentence. We “generally defer to a sen‐

tencing court’s judgment and review the substance of crimi‐

nal sentences only for abuse of discretion.” United States v.

Banas, 712 F.3d 1006, 1009–10 (7th Cir. 2013). A below‐guide‐

lines sentence is presumptively reasonable. See United States

v. Solomon, 892 F.3d 273, 278 (7th Cir. 2018).

The district court calculated Wehrle’s sentencing guide‐

line range as 70 years’ imprisonment. But Wehrle ultimately

received a below‐guidelines sentence of 40 years’ imprison‐

ment. At sentencing the district court heard and weighed the

18 U.S.C. § 3553(a) factors, considering Wehrle’s employment

history, military service, and other mitigating factors as well

as aggravating factors such as the size of his child pornogra‐

phy collection and the severity of harm he inflicted on A.E.

Wehrle points to nothing to overcome the presumptive rea‐

sonableness of his below‐guidelines sentence. His sentence

was therefore substantively reasonable.

For these reasons, we AFFIRM.
No. 19‐2853 13

ST. EVE, Circuit Judge, concurring in part. I join the major‐

ity’s conclusion that Mr. Wehrle’s conviction and sentence

should be affirmed. I further agree that the evidence against

Wehrle was “overwhelming,” and any error by the district

court in admitting Officer Wimmersberg’s testimony was

harmless. I write separately to briefly address the majority’s

conclusion that Officer Wimmersberg’s testimony constituted

expert testimony under Federal Rule of Evidence 702.  

In testifying about her process for extracting images from

Wehrle’s storage devices, Officer Wimmersberg testified to

simply “hook[ing] up” the Defendant’s storage devices to a

write blocker, which “just prevents anything from being writ‐

ten to that device” and then “imag[ing] the drive.” Although

members of the general public may not be familiar with the

particular programs she used to do so, the average person

would be familiar with the concepts of extracting data from a

device and preserving the data on the origin device.   

The majority today concludes that this is expert testimony,

but its analysis is in tension with several decisions by our sis‐

ter circuits, which each conclude that testimony regarding the

mere extraction of data from a cell phone does not require ex‐

pert certification under Rule 702. See United States v. Montijo‐

Maysonet, 974 F.3d 34, 47 (1st Cir. 2020); United States v.

Chavez‐Lopez, 767 F. App’x 431, 433–34 (4th Cir. 2019); United

States v. McLeod, 755 F. App’x 670, 673–74 (9th Cir. 2019); see

also United States v. Marsh, 568 F. App’x 15, 17 (2d Cir. 2014).  

In Montijo‐Maysonet, the First Circuit concluded that an of‐

ficer’s testimony about extracting data from a sex‐crime vic‐

tim’s cell phone was properly admitted, even though the of‐

ficer was not qualified as an expert. 974 F.3d at 47.  There, an

officer testified that “investigators used forensic software to
14 No. 19‐2853

copy the same info from [the defendant’s] phone and display

it on paper.” Id. at 48. The court observed that “These days,

most anyone with a cellphone knows they store information

about text messages, including the sender, recipient, and con‐

tent. You don’t need to be a software engineer to pick up a

cellphone [and access its contents].” Id. at 47. Because of the

public’s familiarity with how to view and retrieve cellphone

messages, the court agreed that the district court did not

abuse its discretion in permitting this testimony without qual‐

ifying the testifying officer as an expert in “cell phone extrac‐

tions of forensic analysis.” See id. at 47–48.  

Similarly, in Chavez‐Lopez, the Fourth Circuit concluded

that an officer’s testimony regarding data extraction from a

cell phone was not expert testimony. 767 F. App’x at 433–35.

The court reasoned that the testimony only “concerned the

actions he took to extract the data.” Id. at 434. So, the officer’s

“role as a witness [was] best characterized as testifying about

facts in his personal knowledge.” Id. Furthermore, the officer

“offered no assurances about how well Cellebrite [the extrac‐

tion program] performed.” Id. The testimony “didn’t require

a technical understanding” of the program, and the officer

only testified about “copying data from one drive to another,

which is ‘the product of reasoning processes familiar to the

average person in everyday life.’” Id. (citations omitted).  

Finally, in United States v. McLeod, the Ninth Circuit found

that any errorin admitting lay testimony regarding the extrac‐

tion of images of child pornography from a defendant’s cell

phone was harmless. See 755 F. App’x at 673. Before conclud‐

ing that such error was harmless, however, the majority opin‐

ion suggested that the lay testimony was permissible for sim‐

ilar reasons as explained in Montijo‐Maysonet and Chavez‐
No. 19‐2853 15

Lopez. See id. (“At trial, Detective Jackson testified about how

he used a Cellebrite device during the course of his investiga‐

tion to download information from one of the victim’s cell

phones onto a thumb drive and then testified about the con‐

tents of that information. He testified about what Cellebrite

does and how he used it in the course of his investigation to

extract information from the victim’s cell phone. ... In short,

Detective Jackson testified about his use and interaction with

Cellebrite—and how he extracted data from one of the vic‐

tim’s phones in this case.”)

Based on the persuasive reasoning by our sister circuits in

the above cases, I would conclude that Officer Wimmers‐

berg’s testimony was proper lay testimony. Although the

above cited cases involve cell phones, and not external storage

devices like the ones at issue here, the distinction does not im‐

pact the analysis given the simplicity of the devices involved,

the familiarity of the public with these kinds of devices, and

the lack of any allegations that the devices were manipulated

to hide or alter their contents. In this case, Officer Wimmers‐

berg’s testimony was limited to her use of simple data preser‐

vation and extraction programs, and she did not opine on the

efficacy or reliability of those programs in general. Moreover,

the concept of preserving data in its original format while

making a copy of that data was well within the public’s un‐

derstanding in 2019, at the time of Wehrle’s trial. Cf. United

States v. Christian, 673 F.3d 702, 708–09 (7th Cir. 2012) (“Lay

testimony results from a process of reasoning familiar in eve‐

ryday life[.]”) (quoting Fed. R. Evid. 701 advisory committee’s

note (2000 amends.)); United States v. Pirosko, 787 F.3d 358, 374

(6th Cir. 2015) (“It is common knowledge that a USB drive

functions as an external storage device. These drives store

files when an individual places those files onto the device.
16 No. 19‐2853

These drives do not come pre‐loaded with child pornogra‐

phy.”).  

There are cases in which the collection of digital data

would require expert testimony due, for example, to the so‐

phisticated nature of the particular forensic analysis or the

equipment deployed, or the technical nature of the testimony.

But this is not one of those cases. Importantly, this is not a case

in which the defendant has allegedly deleted or otherwise

manipulated images of child pornography, see United States v.

Haymond, 672 F.3d 948 (10th Cir. 2012); nor has Defendant

claimed that the images here did not display real children, see

United States v. Fabrizio, 445 F. Supp. 2d 152 (D. Mass. 2006);

nor has Defendant claimed that someone else accessed these

images or videos from his devices, see United States v. Mo‐

reland, 665 F.3d 137 (5th Cir. 2011). Defendant had exclusive

use of the digital storage devices; he lived alone, aside from

the occasional visits from the minor victim, and he does not

claim that the images arrived on his devices by way of errant

googling or auto‐caching, see United States v. Carroll, 886 F.3d

1347 (11th Cir. 2018).   

Based on the particular facts of this case and the abuse of

discretion standard, I would find that the district court did

not abuse its discretion in admitting Officer Wimmersberg’s

testimony as lay testimony. I join the majority’s opinion in all

other respects.