                               In the

    United States Court of Appeals
                 For the Seventh Circuit
                     ____________________
No. 19‐2230
UNITED STATES OF AMERICA,
                                                   Plaintiff‐Appellee,
                                 v.

MICHAEL REES,
                                               Defendant‐Appellant.
                     ____________________

         Appeal from the United States District Court for the
                    Central District of Illinois.
           No. 18‐cr‐10033 — Michael M. Mihm, Judge.
                     ____________________

    ARGUED FEBRUARY 12, 2020 — DECIDED APRIL 30, 2020
                ____________________

   Before BAUER, KANNE, and BARRETT, Circuit Judges.
    KANNE, Circuit Judge. An investigation into online sharing
of child pornography led law‐enforcement oﬃcers to Michael
Rees’s residences and vehicle, where they executed search
warrants and found child pornography. Charged with federal
crimes, Rees moved to suppress the evidence found in the
searches. A district court denied his motion, and Rees then
pled guilty to the charges but reserved his right to appeal the
suppression decision. Appealing that decision, Rees argues
2                                                 No. 19‐2230

that the evidence was inadmissible because the warrants were
invalid and the oﬃcers could not reasonably rely on them to
conduct the searches.
    We aﬃrm for two reasons. First, the warrant‐issuing judge
had a substantial basis for concluding that there was a fair
probability evidence of child‐pornography crimes would be
uncovered in the searches. And second, even if the warrants
were invalid, the oﬃcers executed them in objective good
faith.
                        I. BACKGROUND
    In 2017 and 2018, FBI Child Exploitation Task Force Oﬃcer
William Lynn was investigating the sharing of child pornog‐
raphy through online, peer‐to‐peer networks. Over the course
of six months, his investigation led him to believe child por‐
nography would be found in the college apartment, house,
and pickup truck of 40‐year‐old Michael Rees.
    Seeking warrants to search these places, Oﬃcer Lynn gave
a magistrate a seventeen‐page probable‐cause aﬃdavit,
which described the oﬃcer’s training and experience, law‐en‐
forcement methods for tracking child pornography on peer‐
to‐peer networks, and the specific investigation that steered
him toward Rees’s residences and vehicle.
    Based on Officer Lynn’s affidavit alone, the magistrate is‐
sued the requested warrants. When officers executed them,
they found thousands of still images and almost 200 videos of
child pornography on Rees’s computer. A grand jury charged
Rees with four counts of receiving, and one count of pos‐
sessing, child pornography, 18 U.S.C. § 2252A(a)(2)(A), (5)(B).
   Initially pleading not guilty, Rees moved to suppress the
evidence found in the searches. He argued that the warrants
No. 19‐2230                                                                    3

were invalid for want of probable cause and the officers could
not rely on them in good faith. Unconvinced after a hearing,
the district court denied Rees’s motion. Rees then pled guilty
to all five charges while reserving his right to appeal the sup‐
pression decision. The district court accepted Rees’s guilty
plea, entered a judgment of conviction, and sentenced Rees to
97 months’ imprisonment—a sentence Rees does not contest.
   On appeal, Rees maintains that the warrants were unsup‐
ported by probable cause and could not be relied upon in
good faith.
                                   II. ANALYSIS
    Rees’s appeal challenges only the admissibility of evi‐
dence obtained from warrant‐authorized searches. Our re‐
view of warrant‐authorized searches involves a complex
standard. See United States v. McIntire, 516 F.3d 576, 578 (7th
Cir. 2008).1 But it is simplified in this case because the district
court did not make credibility determinations or findings of
historical fact based on evidence received during the

       1 The precise standard, which we articulated in McIntire, is the follow‐

ing:
       A district court’s findings of historical fact are reviewed for clear
       error, whether or not a warrant issued. Ornelas v. United States, 517
       U.S. 690, 699 (1996). A district judge’s legal conclusions are re‐
       viewed without deference. And on the mixed question whether
       the facts add up to “probable cause” under the right legal stand‐
       ard, we give no weight to the district judge’s decision—for the
       right inquiry is whether the judge who issued the warrant (rarely
       the same as the judge who ruled on the motion to suppress) acted
       on the basis of probable cause. On that issue we must afford “great
       deference” to the issuing judge’s conclusion.
McIntire, 516 F.3d at 578.
4                                                    No. 19‐2230

suppression hearing. See id.; United States v. Koerth, 312 F.3d
862, 865 (7th Cir. 2002). Indeed, the district court confirmed at
the suppression hearing that it would be receiving no evi‐
dence, only argument. As a result, we face just two questions,
each involving a single standard.
   The first question is, did the warrant‐issuing judge act on
the basis of probable cause? See United States v. Aleshire, 787
F.3d 1178, 1178–79 (7th Cir. 2015). On this question, we up‐
hold the magistrate’s finding of probable cause so long as that
judge “had a ‘substantial basis for … conclud[ing]’ that a
search would uncover evidence of wrongdoing.” Illinois v.
Gates, 462 U.S. 213, 236 (1983) (alteration in original) (quoting
Jones v. United States, 362 U.S. 257, 271 (1960)).
    The second question is, if the warrants were invalid, was
the evidence obtained from the searches nevertheless admis‐
sible because the oﬃcers relied on the warrants in objective
good faith? See United States v. Leon, 468 U.S. 897, 922 (1984).
On this question, our review is de novo—again, because the
district court drew only a legal conclusion, without finding
facts or determining credibility. See United States v. Mitten, 592
F.3d 767, 770–71 (7th Cir. 2010).
    A. Probable Cause
    The Fourth Amendment guarantees that “no Warrants
shall issue, but upon probable cause.” U.S. Const. amend. IV.
Rees contends that the warrants here were not issued upon a
proper probable‐cause decision, for three reasons: first, when
ruling on the motion to suppress, the district court inappro‐
priately relied on a demonstrative aid that supplied new in‐
culpatory information; second, Oﬃcer Lynn’s aﬃdavit
No. 19‐2230                                                     5

exposed fatal gaps in his investigation; and third, key infor‐
mation in the aﬃdavit was stale.
    We first dispense with Rees’s demonstrative‐aid argu‐
ment. During the suppression hearing, the government pre‐
sented the district court with a two‐and‐one‐third‐page doc‐
ument condensing the information in Oﬃcer Lynn’s seven‐
teen‐page aﬃdavit. Rees argues that this “complex demon‐
strative aid” did not merely summarize the aﬃdavit but
added inculpatory information to it. He surmises that the dis‐
trict court relied on that new information when denying
Rees’s motion to suppress, and that without the additional in‐
formation, the magistrate (the warrant‐issuing judge) could
not have based the warrants on a finding of probable cause.
    This argument reaches outside the scope of our review.
Our task is to determine whether the magistrate had a sub‐
stantial basis to conclude that probable cause existed. To do
this, we look only at the information the magistrate had. See
Rainsberger v. Benner, 913 F.3d 640, 650 (7th Cir. 2019); United
States v. Harris, 464 F.3d 733, 739 (7th Cir. 2006). The magis‐
trate here had only Oﬃcer Lynn’s aﬃdavit. So, our review
does not encompass the later‐made demonstrative aid or the
district court’s alleged misuse of it.
    We emphasize an important qualification: the demonstra‐
tive aid was not evidence of falsities in the aﬃdavit. Cf., e.g.,
United States v. Roth, 391 F.2d 507, 509 (7th Cir. 1967) (suppres‐
sion hearing included testimony exposing a fatal flaw in the
aﬃdavit). This is germane because—while a district court
may not consider new inculpatory information supporting a
finding of probable cause—the court may (and at times must)
consider new information attacking the veracity of the war‐
rant aﬃdavit or on issues outside whether probable cause
6                                                              No. 19‐2230

existed. See Rainsberger, 913 F.3d at 650 n.5; Harris, 464 F.3d at
738–39. But Rees does not contend that the district court re‐
ceived exculpatory evidence. He argues only that the demon‐
strative aid included inculpatory information outside the aﬃ‐
davit’s four corners and that the added information should
not have contributed to the district court’s decision that the
warrants were valid.
    Whether the demonstrative aid included new inculpatory
information, and whether the district court improperly relied
on it when concluding the warrants were proper, are both be‐
side the probable‐cause inquiry we face today. Our review
concerns only whether the aﬃdavit, alone—the sole basis on
which the magistrate issued the warrants—was enough for
the magistrate to decide that probable cause existed. In other
words, the aﬃdavit’s four corners bound our review. See
United States v. Bell, 585 F.3d 1045, 1049 (7th Cir. 2009)
(“When, as here, the aﬃdavit is the only evidence provided
to the judge in support of the search warrant, the validity of
the warrant rests solely on the strength of the aﬃdavit.”).2
    We turn now to the question at hand: whether the warrant‐
issuing judge had a substantial basis for its probable‐cause de‐
termination. The magistrate’s task was “to make a practical,
common‐sense decision whether, given all the circumstances
set forth in the aﬃdavit before him … there is a fair probabil‐
ity that contraband or evidence of a crime will be found in a
particular place.” Gates, 462 U.S. at 238. Probable cause does


    2 To be clear, had the district court received evidence undermining the

veracity of information in the affidavit, our review would involve another
layer of analysis. See McIntire, 516 F.3d at 578. But that is not the situation
before us.
No. 19‐2230                                                      7

not require a showing of criminal activity, as it rides on “the
degree of suspicion that attaches to particular types of non‐
criminal acts.” Id. at 243 n.13. It also depends on the totality of
the circumstances—“the whole picture”—not each fact in iso‐
lation. District of Columbia v. Wesby, 138 S. Ct. 577, 588 (2018)
(quoting United States v. Cortez, 449 U.S. 411, 417 (1981)).
   Ultimately, the magistrate had to decide whether Oﬃcer
Lynn’s aﬃdavit provided enough information to warrant a
prudent person to believe that criminal conduct has occurred
and that evidence of it would be found in Rees’s residences
and truck. See Gates, 462 U.S. at 238; Whitlock v. Brown, 596
F.3d 406, 411 (7th Cir. 2010). Rees argues that gaps and stale‐
ness in Oﬃcer Lynn’s aﬃdavit required a negative answer.
We disagree. To explain why, we will recapitulate portions of
Oﬃcer Lynn’s aﬃdavit, though we will not provide the same
depth and detail. We will then address Rees’s arguments.
       1. Oﬃcer Lynn’s Aﬃdavit
    Oﬃcer Lynn first gave background information about
peer‐to‐peer file‐sharing networks and his law‐enforcement
experience with them. He recounted some of his and other of‐
ficers’ knowledge about how digital media, including child
pornography, is often stored and distributed through per‐
sonal computers. Notably, he explained that digital media can
often be recovered from devices even after those devices have
been in storage for months or even years; and—due to the na‐
ture of digital devices and the operating systems involved in
peer‐to‐peer sharing—evidence of downloaded files can be
recovered after a user deletes the files from a computer.
   Getting more specific, Oﬃcer Lynn described two peer‐to‐
peer networks that were integral to his investigation:
8                                                  No. 19‐2230

eDonkey and BitTorrent. The two networks are distinct and
rely on diﬀerent software, but both are used to share and
download digital files.
   Oﬃcer Lynn explained that the eMule software, which op‐
erates on the eDonkey network, tracks and gives credit to in‐
dividual users for their sharing activity; and it does so by as‐
signing each network user a unique identifier, or “user hash.”
That user hash allows oﬃcers to see which user is oﬀering to
share particular files.
    BitTorrent works a bit diﬀerently. It enables users to share
sets of files that may be stored across multiple computers. The
sets of files are the “payload” of a “torrent file,” which has a
unique “infohash” identifier. This infohash works as a form
of “digital fingerprinting,” singularly identifying the torrent
file and its corresponding payload. When a user wants to
download a payload, the user connects his or her device to
computers that have the payload’s pieces. The devices con‐
nect via the internet and “ports,” which range in number from
zero to 65,535. Whereas ordinary internet browsing typically
occurs on low‐numbered ports, like port 80, BitTorrent shar‐
ing typically occurs on less‐common, high‐numbered ports,
which decrease the likelihood that the sharing will interfere
with the computers’ other functions.
    In addition to describing these networks, Oﬃcer Lynn de‐
voted a section of his aﬃdavit to how oﬃcers use a law‐en‐
forcement database to track peer‐to‐peer network activity in‐
volving child pornography. He explained that oﬃcers log on
to peer‐to‐peer networks, and when they find files containing
child pornography, the oﬃcers record—in the database—var‐
ious information about the transfer of those files. That infor‐
mation includes the IP addresses of computers involved in the
No. 19‐2230                                                      9

transfer, the date and time the files were shared, the file names
and infohashes, and identifying information about the users
engaged in the transaction. Multiple law‐enforcement agen‐
cies use this common database to record, store, and share in‐
vestigative information about peer‐to‐peer dissemination of
child pornography.
    Oﬃcer Lynn also noted that another resource, a law‐en‐
forcement reference library, stores child‐pornography files for
use in child‐pornography investigations. By matching the in‐
fohash of a shared torrent file to the infohash of a file or set of
files in the library, Oﬃcer Lynn understood that the shared
torrent payload and the corresponding files in the library
have the same content.
   Against this technical background, Officer Lynn charted
the investigation that homed in on Rees’s residences and
truck.
    In October 2017, Officer Lynn logged on to the BitTorrent
network and connected his computer to a “suspect” device.
He began investigating this particular device because it was
associated with a BitTorrent file that had a payload containing
child pornography or child erotica. In a series of connections,
Officer Lynn’s computer—which was running investigative
software—reported that the suspect device had all pieces of a
payload for another torrent file. That torrent file’s infohash
matched one in the law‐enforcement reference library, which
informed Officer Lynn that the payload included 32 images
of a child engaging in sexually explicit conduct.
    Officer Lynn recorded the suspect device’s IP address and
learned through an administrative subpoena that the address
was assigned to a 32‐unit apartment complex near Illinois
10                                                  No. 19‐2230

State University. To differentiate between individual apart‐
ment units’ internet activity going forward, officers installed
a tracking system on the complex’s internal network, which
assigned a different internal IP address to each apartment
unit.
    Next, Officer Lynn drew upon investigatory information
recorded in the law‐enforcement database. He noticed that,
before the internal‐network tracker was installed at the apart‐
ment complex, an officer had logged eDonkey activity taking
place at the complex’s IP address. The same user hash for that
activity had also been logged in the database for eDonkey ac‐
tivity at another IP address, which was assigned to Michael
Rees for a single‐family home in Pekin, Illinois. Rees’s driver’s
license likewise listed the Pekin address as his residence. The
eDonkey activity logged for Rees’s home IP address took
place during the university’s mid‐year break, on January 8,
2018. Rees’s home IP address was also logged in the law‐en‐
forcement database for BitTorrent activity on the same day,
January 8.
    Officer Lynn soon learned that Rees had leased one of the
32 apartments near the university for the 2017–18 academic
year. As a result, the officers narrowed their internal‐network
tracking to monitor internet usage of only Apartment 8, the
apartment Rees had leased with three other residents.
    During the spring semester, in March 2018, Officer Lynn
observed a recent database entry for BitTorrent activity at the
apartment complex’s IP address. The database indicated that
the activity occurred through port 22,863. The internal‐net‐
work tracker showed that the same numbered port was used
at the same time by someone at Apartment 8.
No. 19‐2230                                                   11

   Finally, state records revealed that Rees had a white
pickup truck, which, Officer Lynn explained, was seen
parked near both Rees’s apartment and his Pekin home.
    Officer Lynn submitted that, based on the information he
retailed in the affidavit, probable cause existed to believe that
evidence of crimes concerning child pornography would be
found in Rees’s apartment, house, and truck.
       2. Gaps and Staleness
    Rees points to a number of holes in the investigation de‐
scribed in Officer Lynn’s affidavit. He also argues that Officer
Lynn’s findings grew stale before the search warrants issued.
    Specifically, Rees points out that anyone at the apartment
complex could have downloaded the October 2017 payload
that Officer Lynn’s computer reported was located on the sus‐
pect device. He adds that Officer Lynn did not actually open
the files downloaded in October 2017; the officer instead com‐
pared the payload’s infohash to that of files in a reference li‐
brary. Rees also asserts that the affidavit did not clarify that
the law‐enforcement database includes only information
about files that officers have recognized contain child pornog‐
raphy. He reasons that Officer Lynn first described a “peer‐
to‐peer database” and then referred to the “ICAC Cops data‐
base” when charting his investigation; the affidavit did not
explicitly state that the two terms refer to the same database—
the one Officer Lynn described as storing information on the
sharing of child pornography. Rees additionally reminds us
that child erotica, which may have prompted Officer Lynn’s
initial inquest into the suspect device’s activities, is not con‐
traband. He continues that Officer Lynn did not personally
view the files shared in the peer‐to‐peer activity that officers
12                                                   No. 19‐2230

tied to Rees’s apartment and house, specifically. And he lastly
urges that the criminal activity Officer Lynn observed in Oc‐
tober was stale by the time he applied for the affidavits six
months later.
    These are strong reasons why Officer Lynn had not
proven, in the affidavit, that Rees received and possessed
child pornography in his apartment, house, and truck. But
probable cause is a low bar that can be cleared without a prima
facie showing of criminal activity. See Gates, 462 U.S. at 235,
243 n.13. Again, what matters is the degree of suspicion that
arises from particular types of noncriminal acts, taken alto‐
gether. Id. at 243 n.13.
    Here, the affidavit did not establish an airtight case against
Rees. But it supplied plenty of information for a prudent per‐
son to believe child pornography would be found in Rees’s
homes and truck. Although Officer Lynn’s investigation be‐
gan with a suspicion that a certain device was associated with
child pornography or child erotica (which is not contraband),
the next step in his investigation gave strong indication that
the suspect device contained images of child pornography,
not just child erotica. By connecting his computer to the sus‐
pect device in October, and by comparing the infohash of the
files downloaded by the suspect device to the infohash of
child‐pornography files in the reference library, Officer Lynn
had good reason to believe the suspect device’s user had
downloaded child pornography.
   Next, Officer Lynn located the suspect device at the 32‐
unit apartment complex. He did this by tracking down the ge‐
ographic location of the IP address that the suspect device
used to download the contraband files. Further funneling the
investigation to more precisely locate the device, Officer Lynn
No. 19‐2230                                                    13

saw that the law‐enforcement database indicated the same
eDonkey user had engaged in child‐pornography sharing
both at the apartment complex and at Rees’s house, where
(the law‐enforcement database informed him) BitTorrent ac‐
tivity concerning child pornography also took place. Officer
Lynn later learned that Rees resided at both locations.
    Finally, suspicion mounted around Apartment 8 when Of‐
ficer Lynn learned, based on database entries, that someone
at the complex had shared child pornography using port
22,863. And the internal‐network tracker showed that, at the
same time, someone was using the same uncommon, high‐
numbered port via the internal IP address of Apartment 8:
Rees’s apartment. Finally, Rees’s truck was seen at both resi‐
dences.
    Despite the imperfections Rees identifies, all the infor‐
mation in the affidavit is enough for a reasonable person to
believe that evidence of child‐pornography crimes would be
found in Rees’s apartment, house, and truck.
   Rees’s argument about staleness does not change this con‐
clusion. He argues that the affidavit’s information about the
October 2017 downloads was stale by the time Officer Lynn
sought the warrants in late March 2018. Because that key in‐
formation was stale, he says, the affidavit did not support a
finding of probable cause. We disagree for two reasons.
    First, the information about the October 2017 downloads
was supported by more recent peer‐to‐peer activity logged in
the law‐enforcement database, which suggested that the same
kind of criminal activity continued into March 2018. See
United States v. Pless, 982 F.2d 1118, 1126 (7th Cir. 1992) (“Pas‐
sage of time is less critical when the affidavit refers to facts
14                                                      No. 19‐2230

that indicate ongoing continuous criminal activity.”). Officer
Lynn indicated—when describing the law‐enforcement data‐
base—that officers used the database to “log information re‐
garding child pornography trading on the peer‐to‐peer net‐
work.” He explained that the information recorded in the da‐
tabase stemmed from the sharing of files identified by law‐
enforcement officers as “child pornography file[s],” which
meant that the database provided “a historical record of com‐
puters that have offered the child pornography file for down‐
load.” So, the later logged entries of peer‐to‐peer activity con‐
nected to Rees’s home and apartment could reinforce a belief
that the originally detected criminal activity was ongoing.
    Second, even if more recent information did not refresh
Officer Lynn’s initial observations of criminal conduct, that
information from October 2017 did not go stale over six
months. We have not identified a precise expiration time for
an affidavit’s information. That’s because probable cause is a
“fluid concept,” Gates, 462 U.S. at 232, and the recency of in‐
formation given to the issuing judge is just one factor in the
totality‐of‐the‐circumstances probable‐cause inquiry, United
States v. Carroll, 750 F.3d 700, 703 (7th Cir. 2014). But we have
recognized that evidence contained in computer equipment
does not rapidly dissipate or degrade, that child‐pornography
collections tend to be kept for long periods of time, and that
digital information is often retrievable from hard drives even
after a user “deletes” it. See id. at 704–05; United States v. Seiver,
692 F.3d 774, 776 (7th Cir. 2012). So, information regarding
digital child‐pornography files may stave off staleness for
years. See, e.g., Carroll, 750 F.3d at 706 (five years); United States
v. Newsom, 402 F.3d 780, 783 (7th Cir. 2005) (one year); see also
Carroll, 750 F.3d at 704–05 (listing cases from other circuits).
No. 19‐2230                                                   15

    Officer Lynn confirmed that the devices and operating
systems involved in peer‐to‐peer sharing allow officers to re‐
cover information about network activity even after a user de‐
letes specific files or has kept a device in storage for months
or years. He also revealed how peer‐to‐peer networks allow
users to access the same or similar child‐pornography files
without keeping them on their own computers: the users can
relocate files on the network and download them again and
again. In this way, peer‐to‐peer networks may, in some cases,
extend the time before which certain evidence of child‐por‐
nography crimes goes stale—because the evidence may be
stored across a greater number of electronic devices. See
Seiver, 692 F.3d at 778 (stressing that inquiries into staleness
and child‐pornography collectors must be grounded “in a re‐
alistic understanding of modern computer technology and
the usual behavior of its users”).
    Of course, at some point “after a very long time” the like‐
lihood that certain digital information will be recoverable
from a specific device “drops to a level at which probable
cause to search the suspect’s home for the computer can no
longer be established.” Id. at 777. But Rees has not shown that
this is an “exceptional case,” id. at 778, in which a delay be‐
tween the electronic transfer of an image and Officer Lynn’s
requests to search for evidence of child‐pornography crimes
“destroy[ed] probable cause to believe that a search of the
computer will turn up the evidence sought,” id. at 777. Ac‐
cordingly, staleness did not prevent the magistrate from ap‐
propriately finding probable cause.
   All‐in‐all, the affidavit supplied a substantial basis for the
magistrate to conclude that the requested searches had a fair
probability of uncovering evidence of child‐pornography
16                                                   No. 19‐2230

crimes. This is enough to affirm the district court’s denial of
Rees’s motion to suppress. But there is another reason Rees is
not entitled to relief.
     B. Good Faith
    Even if the search warrants lacked a basis in probable
cause, the exclusionary rule does not operate against the evi‐
dence if the good‐faith exception applies—that is, if the offic‐
ers who executed the warrants relied, in objective good faith,
on the magistrate’s probable‐cause decision. See Leon, 468 U.S.
at 922–24.
     Officer Lynn’s choice to obtain the warrants in the first
place invokes a presumption that he acted in good faith. See
United States v. Lickers, 928 F.3d 609, 618 (7th Cir. 2019). To
overcome this presumption, Rees must show the existence of
a situation in which the good‐faith exception does not apply,
see id.; United States v. Glover, 755 F.3d 811, 818–19 (7th Cir.
2014); four such situations are well established: (1) the affiant
misled the magistrate with information the affiant knew was
false or would have known was false but for the affiant’s reck‐
less disregard for the truth; (2) the magistrate wholly aban‐
doned the judicial role and instead acted as an adjunct law‐
enforcement officer; (3) the affidavit was bare boned, “so lack‐
ing in indicia of probable cause as to render official belief in
its existence entirely unreasonable”; and (4) the warrant was
so facially deficient in particularizing its scope that the offic‐
ers could not reasonably presume it was valid, Leon, 468 U.S.
at 923 (quoting Brown v. Illinois, 422 U.S. 590, 611 (1975) (Pow‐
ell, J., concurring in part)).
   Rees does not argue that the warrants lacked adequate
particularity, rendering them facially deficient. Instead, he
No. 19‐2230                                                               17

argues some conglomerate of the other three. Hard‐pressed to
say the detailed, seventeen‐page affidavit was bare boned,
Rees contends that Officer Lynn omitted clarifying infor‐
mation, which left the magistrate confused and misled into
believing probable cause existed. Echoing his arguments for
why probable cause was lacking, he says that the affidavit
failed to highlight the fact that Officer Lynn neither opened
the files downloaded in October 2017 nor confirmed that the
peer‐to‐peer activity recorded thereafter involved child por‐
nography.
    Although this information could have been clearer, Officer
Lynn supplied it to the magistrate. And, for reasons we’ve al‐
ready explained, this information did not prevent the magis‐
trate from properly finding probable cause. Even if it did,
though, the indicia of probable cause were not so lacking that
official belief in its existence was unreasonable. And Rees has
not shown that the alleged failure to spotlight certain infor‐
mation resulted from reckless disregard for the truth.3 So,
Rees has not overcome the presumption of good faith with his
first arguments.
    Finally, resuscitating his focus on the demonstrative aid,
Rees says the affidavit was too technical and confusing for the
magistrate to have functioned as anything but a rubber stamp
for law enforcement. After all, he reasons, the district court



    3 Rees has neither argued nor established that he is entitled to a Franks

hearing, which requires a “substantial preliminary showing” that (1) the
affidavit had a material falsity or omission that would alter the probable‐
cause determination, and (2) the falsity or omission was made “knowingly
and intentionally, or with reckless disregard for the truth.” Franks v. Dela‐
ware, 438 U.S. 154, 155–56 (1978); see Glover, 755 F.3d at 820.
18                                                  No. 19‐2230

relied on the government’s demonstrative aid to navigate the
affidavit’s content.
    Even if the district court used the demonstrative aid—
something we do not decide—that alone would not establish
that the magistrate was unable to understand Officer Lynn’s
affidavit and carry out his judicial role. The affidavit provided
detailed, comprehensible descriptions of both the relevant
technology and the investigative steps officers took. So, Rees
has not shown that the affidavit was so befuddling that the
magistrate must have abandoned his neutral, detached role.
                         III. CONCLUSION
    Because the magistrate had a substantial basis for conclud‐
ing probable cause existed to search Rees’s residences and
truck, and because the oﬃcers executing the searches could
rely on the warrants in objective good faith, we AFFIRM the
denial of Rees’s motion to suppress.
