                              In the

    United States Court of Appeals
                For the Seventh Circuit
                    ____________________
No. 15-2008
UNITED STATES OF AMERICA,
                                                 Plaintiff-Appellee,

                                v.

AARON THOMPSON,
                                             Defendant-Appellant.
                    ____________________

        Appeal from the United States District Court for the
                   Western District of Wisconsin.
       No. 3:14-CR-00090-1 — William M. Conley, Chief Judge.
                    ____________________

  ARGUED DECEMBER 16, 2015 — DECIDED FEBRUARY 1, 2016
               ____________________

   Before MANION, KANNE, and WILLIAMS, Circuit Judges.
   KANNE, Circuit Judge. An informant working for a drug
task force bought crack from Aaron Thompson at the apart-
ment where Thompson was staying. The informant was
equipped with two hidden audio-video recording devices
that captured the transaction. Thompson moved to suppress
the video recordings because, he said, the surreptitious re-
cordings constituted an unlawful search in violation of the
Fourth Amendment. The district court disagreed on the
2                                                No. 15-2008

ground that Thompson had invited the informant into the
apartment, thus forfeiting his expectation of privacy as to
anything he voluntarily disclosed. For the reasons that fol-
low, the judgment of the district court is affirmed.
    Investigators enlisted the informant to arrange and carry
out a drug transaction in La Crosse, Wisconsin. The
informant called a telephone number investigators knew to
be associated with the Knox brothers. (The police were in-
vestigating the four Knox brothers for drug-related crimes
and had identified the apartment from which they were
dealing drugs.) The informant told the male who answered
the phone that he had four bills—$400—and wanted to buy
drugs. The man on the other end of the line told the
informant to come over. Investigators equipped the
informant with three devices: an audio-video recorder posi-
tioned at neck height (commonly referred to as a “button
cam”); an audio-video recorder that stayed at waist height
(the camera appears to be attached to a set of keys); and an
audio recorder. Investigators also gave the informant $400 in
marked bills.
    The video recordings showed what happened next. The
informant approached the apartment building where the
transaction was set to take place and knocked on the door of
Apartment 4. Thompson opened the door and invited the
informant into the apartment. The informant handed
Thompson $400. Thompson turned and walked across the
room to what the informant thought was the bathroom.
Thompson cracked open the door, and reached inside. A
person inside the bathroom handed an item to Thompson.
   At the same time, another man in the living room told
Thompson that he was leaving. Before he departed he
No. 15-2008                                                 3

turned on the microwave. He told Thompson to “let that shit
cook all the way” and to ice it down and let it cool after the
microwave stopped. The man then left the apartment.
   A short while later, Thompson handed the informant
what he said was “twelve.” The informant then left the
apartment.
    Afterward when the police officers discussed the encoun-
ter with the informant, he added several details not captured
on video or audio. He said he had heard two men in the
bathroom when Thompson opened the door and passed the
$400 inside. What Thompson had received in return, the in-
formant explained, was a sandwich bag holding several
smaller plastic bags of crack, from which he removed 12.
(Lab tests confirmed that the smaller bags contained a total
of 2.6 grams of crack.) The informant also said that the item
placed in the microwave was a large “soup bowl” filled
halfway with what he believed to be cocaine. The informant
also saw a box of baking soda sitting next to the microwave.
The informant believed that the man was cooking crack in
the apartment.
   At no point during the transaction did the informant
move from the spot where he was standing directly inside
the front door. From that vantage point the entire living
room and kitchen, as well as the bathroom door, were within
sight of the informant and his two video cameras. Two other
doors, both open, led off the living room, but the videos are
too grainy to see inside those rooms, and the informant did
not mention what, if anything, he could see through those
doorways.
4                                                   No. 15-2008

    After the informant returned from the apartment, one of
the investigators applied to a state judge for a search war-
rant. The officer relayed what the informant had told him
during the debriefing. The officer disclosed the fact that the
encounter was recorded on video, but recounted only the
informant’s observations rather than the content of the
videos. Nothing in the record indicates that the state judge
watched those videos before issuing the search warrant. The
search warrant was executed shortly after it was issued, and
8.3 grams of crack were found in the apartment. Thompson
was arrested at the scene. Federal prosecutors charged him
with one count of distributing the crack to the informant and
a second count of possessing for distribution the crack found
during execution of the search warrant. See 21 U.S.C.
§ 841(a)(1).
    Thompson moved to suppress the two video recordings
taken by the informant, but he did not challenge the legality
of the search warrant or move to suppress the drugs found
in the apartment. He argued that making those surreptitious
recordings invaded his privacy in violation of the Fourth
Amendment. Thompson theorized that video recording is a
greater invasion of privacy than audio recording because, he
said, more information can be captured on video. He also
argued that, despite his consent to the informant’s presence
in the apartment, the informant had exceeded the “license”
granted him to be in the apartment, and thus became a tres-
passer, by secretly videotaping the encounter.
    A magistrate judge recommended that Thompson’s mo-
tion be denied. See 28 U.S.C. § 636(b)(1)(B). Thompson filed
objections, see id. § 636(b)(1), but while those objections still
were pending, he entered a conditional guilty plea to dis-
No. 15-2008                                                    5

tributing the crack to the informant, while reserving the
right to challenge on appeal any adverse decision by the dis-
trict court on his motion to suppress. Later the district court
accepted the magistrate judge’s recommendation, reasoning
that Thompson had forfeited any privacy interest in what he
voluntarily exposed to the informant. The judge pointed out
that the videos had not captured anything that the informant
couldn’t see with the naked eye. Moreover, the judge said,
every federal appellate court to decide the issue had con-
cluded that there is no constitutionally relevant distinction
between secret audio and video recordings when the in-
formant gathers the information from a location where he is
lawfully entitled to be.
   The district judge then sentenced Thompson to 36
months’ imprisonment, significantly below the guidelines
range of 151 to 188 months. The guidelines range was based
on Thompson’s status as a career offender because of two
convictions for a controlled substance offense. See U.S.S.G.
§ 4B1.1(a). But the district judge exercised his discretion un-
der United States v. Corner, 598 F.3d 411, 415–16 (7th Cir.
2010), to go below that range because he believed that
Thompson’s convictions and limited past incarceration did
not warrant such a long prison sentence.
    Thompson makes two arguments challenging the denial
of his motion to suppress the videos. First, under the tres-
pass theory articulated in United States v. Jones, 132 S. Ct. 945
(2012), Thompson argues that the informant exceeded the
scope of his license to be in the apartment as an invitee when
he recorded videos of the encounter. Second, he argues that
making the video recordings violated his reasonable expec-
tation of privacy because the information they revealed was
6                                                  No. 15-2008

not voluntarily disclosed. We have not decided whether
making a covert video recording, as opposed to an audio re-
cording, violates a person’s reasonable expectation of priva-
cy, but three other circuits have concluded that it does not.
See United States v. Wahchumwah, 710 F.3d 862, 866–68
(9th Cir. 2013); United States v. Brathwaite, 458 F.3d 376, 379–
81 (5th Cir. 2006); United States v. Davis, 326 F.3d 361, 364–67
(2d Cir. 2003). We agree with these courts.
    Thompson has never challenged the search warrant or
moved to suppress the drugs recovered during its execution,
which leaves us puzzled about the point of this appeal. Evi-
dence might be inadmissible if discovered while executing a
search warrant that rests principally on information ob-
tained illegally. See United States v. Scott, 731 F.3d 659, 664
(7th Cir. 2013); United States v. Oakley, 944 F.2d 384, 386
(7th Cir. 1991). But a search warrant based partly on tainted
evidence will “still support a search if the ‘untainted infor-
mation, considered by itself, establishes probable cause for
the warrant to issue.’” United States v. Gray, 410 F.3d 338, 344
(7th Cir. 2005) (quoting Oakley, 944 F.2d at 386). Here, the in-
formant gave statements to police about what he heard and
saw in the apartment. When the officer applied for the
search warrant, he testified only about information that
could have been gleaned from the reliable informant’s
statements, without watching the video evidence. And there
is no argument that the use of the informant was unlawful.
So the videos, for all practical purposes, did not contribute to
the finding of probable cause for the search warrant, and
thus the 8.3 grams of crack found while executing the war-
rant could not possibly be subject to suppression even if the
videos might be.
No. 15-2008                                                  7

    Nevertheless, Thompson seeks to suppress the video ev-
idence on Fourth Amendment grounds, and we address
each of his arguments in turn. The Fourth Amendment pro-
tects “[t]he right of the people to be secure in their persons,
houses, papers, and effects, against unreasonable searches
and seizures.” U.S. Const. amend. IV. Warrantless searches,
unless they fall into a recognized exception, are
unreasonable. See Katz v. United States, 389 U.S. 347, 357
(1967); United States v. DiModica, 468 F.3d 495, 499 (7th Cir.
2006). A search occurs either when the government physical-
ly intrudes without consent upon “‘a constitutionally pro-
tected area in order to obtain information,’” Jones, 132 S. Ct.
at 951 (quoting United States v. Knotts, 460 U.S. 276, 286
(Brennan, J., concurring), or “when an expectation of privacy
that society is prepared to consider reasonable is infringed,”
United States v. Karo, 468 U.S. 705, 712 (1984) (quoting United
States v. Jacobsen, 466 U.S. 109, 113 (1984)). Thompson first
argues that the video recordings were obtained in violation
of the Fourth Amendment because, he insists, the informant
exceeded the scope of his license to be in the apartment.
Thompson does not dispute that he invited the informant
into the apartment. But, says Thompson, the license he gave
the informant to enter the apartment did not extend to the
informant’s specific purpose of visually recording the inter-
action. See Florida v. Jardines, 133 S. Ct. 1409, 1416 (2013)
(“The scope of a license—express or implied—is limited not
only to a particular area but also to a specific purpose.”). In
Jardines, the Supreme Court held that the use of a narcotics-
detection dog by police on the front porch of a home consti-
tuted an unreasonable search because taking the dog onto
the porch “reveal[ed] a purpose to conduct a search, which
is not what anyone would think [the officers] had license to
8                                                  No. 15-2008

do.” Id. at 1417. The Court explained that “the background
social norms that invite a visitor to the front door do not in-
vite him there to conduct a search.” Id. at 1416.
    Thompson’s reliance on Jardines is unconvincing. It is
firmly established that the government may use informants
and that an informant’s failure to disclose his true identity
does not render consent to his presence invalid. See Hoffa v.
United States, 385 U.S. 293, 302 (1966); Lewis v. United States,
385 U.S. 206, 208–09 (1966); United States v. Scherer, 673 F.2d
176, 182 (7th Cir. 1982). Moreover, “[t]he mere purpose of
discovering information in the course of engaging in …
permitted conduct does not cause it to violate the Fourth
Amendment.” Jardines, 133 S. Ct. at 1416 n.4 (internal quota-
tion marks and citation omitted); see Kyllo v. United States,
533 U.S. 27, 32 (2001) (“[V]isual observation is no ‘search’ at
all.”). And when the informant discovers information from
where he is lawfully entitled to be, the use of a recording
device to accurately capture the events does not vitiate the
consent or otherwise constitute an unlawful search. See Jones,
132 S. Ct. at 952 (citing On Lee v. United States, 343 U.S. 747,
751–52 (1952), for the proposition that no search or seizure
occurs “where an informant, who was wearing a concealed
microphone, was invited into the defendant’s business”);
Lopez v. United States, 373 U.S. 427, 439 (1963) (explaining
that recording by undercover agent is permissible where
“the device was not planted by means of an unlawful physi-
cal invasion … and it neither saw nor heard more than the
agent himself”); United States v. Eschweiler, 745 F.2d 435, 438
(7th Cir. 1984) (“We know from Lopez that in order to be ef-
fective the consent did not have to extend to [the
informant’s] being wired.”).
No. 15-2008                                                      9

    Here, Thompson invited the informant into the apart-
ment for the purpose of engaging in a drug transaction.
While there, the informant did not “see, hear, or take any-
thing that was not contemplated” as part of the illegal drug
transaction. See Lewis, 385 U.S. at 210; see also Scherer, 673
F.3d at 182. That the informant recorded his observations on
video did not transform the consensual encounter into a
search for purposes of the Fourth Amendment.
    Thompson next contends that making the videos consti-
tuted a search because he had a reasonable expectation of
privacy in the information captured by the recordings, and
had not voluntarily disclosed that information to the in-
formant. This argument is frivolous. The expectation of pri-
vacy does not extend to “[w]hat a person knowingly exposes
to the public, even in his own home or office.” Katz, 389 U.S.
at 351; see Scott, 731 F.3d at 664. Nor does a person have a
privacy interest in what he voluntarily discloses to an in-
formant. See Hoffa, 385 U.S. at 300–02; United States v. White,
401 U.S. 745, 749 (1971) (“[H]owever strongly a defendant
may trust an apparent colleague, his expectations in this re-
spect are not protected by the Fourth Amendment when it
turns out that the colleague is a government agent regularly
communicating with the authorities.”). Thus, once
Thompson invited the informant into the apartment, he “for-
feited his privacy interest in those activities that were ex-
posed to [the informant].” Davis, 326 F.3d at 366;
see Wahchumwah, 710 F.3d at 867; Brathwaite, 458 F.3d at 380–
81; see also United States v. Lee, 359 F.3d 194, 201 (3d Cir. 2004)
(“The principle underlying the governing Supreme Court
cases is that if a defendant consents to the presence of a per-
son who could testify about a meeting and is willing to re-
veal what occurs, the defendant relinquishes any legitimate
10                                                No. 15-2008

expectation of privacy with respect to anything the testimo-
ny could cover.”).
    Moreover, it is well established that in identical circum-
stances an audio recording taken by an informant would not
transform his actions into a search. See White, 401 U.S. at 751
(“If the conduct and revelations of an agent operating with-
out electronic equipment do not invade the defendant’s con-
stitutionally justifiable expectations of privacy, neither does
a simultaneous recording of the same conversations made by
the agent … .”); In re John Doe Trader Number One, 894 F.3d
240, 243–45 (7th Cir. 1990). Thompson argues, though, that a
video recording involves a greater intrusion on privacy be-
cause more information and detail is captured than with an
audio recording. But this distinction, even if theoretically
true, is irrelevant to the extent that an informant or under-
cover agent is using surveillance equipment that’s no more
sensitive than the human ear or eye. Cf. Kyllo, 533 U.S. at 33–
34 (“[O]btaining by sense-enhancing technology any infor-
mation regarding the interior of the home that could not
otherwise have been obtained without physical intrusion in-
to a constitutionally protected area constitutes a search—at
least where … the technology in question is not in general
public use.”) (citation and quotation marks omitted)).
    The video cameras in this case captured nothing more
than what the informant could see with his naked eye. In
fact, the videos are of such poor quality that many of the
things the informant reportedly saw are not readily apparent
on the recordings, including the existence and size of the
bowl placed in the microwave, the contents of the large
sandwich bag handed to Thompson through the bathroom
door, and the box of baking soda next to the microwave.
No. 15-2008                                                              11

Perhaps Thompson anticipates that rapidly evolving tech-
nology soon will allow informants to see through opaque
surfaces or into areas remote from their location or not visi-
ble to the eye.*
    That concern is not for us to address today. And, as al-
ready discussed, Thompson retained no privacy interest in
the areas captured by the camera. The informant would have
been permitted to testify to the things he saw in Thompson’s
apartment, just as he would have been able to testify about
the content of the conversations he had or heard. See Hoffa,
385 U.S. at 302–03; Brathwaite, 458 F.3d at 381; Davis, 326 F.3d
at 367. Just because the informant made video recordings,
Thompson cannot escape the long-standing principle that a
person does not have a constitutional right “to rely on possi-
ble flaws in the agent’s memory, or to challenge the agent’s
credibility without being beset by corroborating evidence
that is not susceptible of impeachment.” Lopez, 373 U.S. at
439; see Davis, 326 F.3d at 367.
  Accordingly, the judgment of the district court is
AFFIRMED.




*For example, development is underway for a hyperspectral camera that
can see through surfaces and can be used with a cellphone camera.
See The $50 hypercam that could give your phone ‘X-ray vision’ to see inside
objects, http://www.dailymail.co.uk/sciencetech/article-3275044/The-50-
hypercam-phone-X-ray-vision-inside-objects-tell-fruit-ripe.html.
