                               In the

    United States Court of Appeals
                 For the Seventh Circuit
                     ____________________
No. 14-1641
TEREZ COOK,
                                                 Plaintiff-Appellant,

                                 v.

ANTHONY O’NEILL and TODD BALDWIN,
                                              Defendants-Appellees.
                     ____________________

        Appeal from the United States District Court for the
                   Eastern District of Wisconsin.
        No. 09-CV-87 — Patricia J. Gorence, Magistrate Judge.
                     ____________________

   ARGUED AUGUST 4, 2015— DECIDED SEPTEMBER 23, 2015
                     ____________________

   Before POSNER, KANNE, and HAMILTON, Circuit Judges.
    POSNER, Circuit Judge. The plaintiff, a prison inmate, filed
suit under 42 U.S.C. § 1983 against two Marinette County
(Wisconsin) Sheriff’s Department detectives, accusing them
of having arrested him in violation of his Fourth Amend-
ment rights. He seeks $25,000 in compensatory and $50,000
in punitive damages for the arrest and accompanying deten-
tion, seizure of personal property that he claims was worth
$10,000, and infliction of emotional distress.
2                                                 No. 14-1641


    He had committed an ugly home robbery in 2005 and
been arrested nine days later in the apartment of a girlfriend,
later his fiancée, Stacy Thede. Convicted in a Wisconsin state
court of armed robbery, armed burglary, battery, theft of
moveable property, mistreatment of an animal resulting in
the animal’s (a dog’s) death, and false imprisonment, he was
sentenced to 40 years in prison to be followed by 18 years of
extended supervision.
    In the present case, the civil case, the defendant officers
moved for summary judgment on the ground that Thede
had consented to their entry into the apartment, where they
had discovered and arrested Cook. When asked at Cook’s
criminal trial whether she’d “let them [the officers] in,”
Thede had testified “Yes,” but in the civil case she submitted
an affidavit which states that when she had testified that she
“let them in” she had meant that she “did not tell them to
leave or did not object directly to them, but let them re-
main.” The district court granted summary judgment for the
officers on the basis of their defense of consent, rejecting
Thede’s affidavit as inconsistent with her testimony at the
criminal trial.
   The two detectives from Marinette County, accompanied
by two officers from the Sheboygan City Police Department
who are not defendants in Cook’s suit, had arrived at
Thede’s apartment house at about 11:00 a.m. on May 31,
2005. The apartment house was in Sheboygan, though the
robbery had occurred in Peshtigo, in Marinette County in
northeastern Wisconsin, more than 150 miles from She-
boygan. That’s why the detectives were from Marinette
County but the other officers were from Sheboygan—they
No. 14-1641                                                   3


would be familiar with the city and provide security for the
detectives.
    The detectives wanted to talk to Thede because they’d
discovered that Cook’s robbery accomplice had been carry-
ing a cellphone when he was arrested and a search of the
cellphone had revealed calls to a phone registered to Thede.
According to their affidavits, the detectives thought the cell-
phone might have been used by the other suspect (who
turned out to be Cook) on the night of the robbery. At the
time, the detectives did not know that suspect’s legal name
but knew that he went by “BN” (short for “Bad News”) and
by “Rex,” since a witness had reported obtaining gloves and
duct tape for “BN” (also known as “Rex”) and driving with
him to and from the robbery site.
    The detectives buzzed for Thede at the building entrance.
In response, without asking who they were, she pushed the
button in her apartment that enabled entry to the building
and met them in the hallway outside the apartment. Explain-
ing that they needed to ask her some questions, they asked
her whether there was anyone in the apartment. According
to Thede and some contemporary police reports (including
the report of one of the two Marinette detectives), she said
yes, “a friend.” According to the other detective, and to a
later affidavit by the detective whose initial report had said
that Thede had not named her friend, she had told them that
“News” was in the apartment.
    Thede asked the detectives in the hall whether she could
reenter her apartment and change out of her pajamas before
talking further with them. They said she could. She reen-
tered, and either closed the door to the apartment or left it
ajar. The officers opened the door (or if it was already slight-
4                                                     No. 14-1641


ly open, opened it further) in order to be able to see into the
apartment. They heard her talking to someone in another
room, and while standing in the doorway without as yet
having entered the apartment they yelled that she should
bring the person she was talking to (who was Cook, with
whom she was talking in a bedroom) into the living room
where the officers could see him. When he appeared, they
recognized him as the robbery suspect. They then entered
the apartment. Within minutes the Sheboygan police officers
arrested him after a warrant check revealed an outstanding
arrest warrant against him for violating parole.
    The district court refused to consider Thede’s affidavit,
which we mentioned earlier, as evidence in this case on the
ground that it was a “sham.” A “sham affidavit” is an affi-
davit that is inadmissible because it contradicts the affiant’s
previous testimony (here, testimony Thede had given in the
criminal prosecution of Cook) unless the earlier testimony
was ambiguous, confusing, or the result of a memory lapse.
Pourghoraishi v. Flying J, Inc., 449 F.3d 751, 759 (7th Cir. 2006);
Bank of Illinois v. Allied Signal Safety Restraint Systems, 75 F.3d
1162, 1168–71 (7th Cir. 1996). Thede’s affidavit was amplifi-
cation rather than contradiction, and so was not within the
“sham” exclusionary rule. But the affidavit doesn’t help
Cook’s case. It acknowledges that Thede agreed to speak
with the officers, and although it says that she agreed to
speak with them in the hallway it must have been obvious to
her that the conversation was more likely to take place in the
apartment than in the hallway outside it. What reason
would she have to talk to four police officers in a public cor-
ridor—except to conceal Cook? But whether she consented
to talk to them only in the hallway is irrelevant, because no
conversation took place; it would have been about Cook’s
No. 14-1641                                                 5


whereabouts, which the officers discovered the moment they
saw him. Thede’s affidavit was therefore inadmissible,
though not because it was a sham affidavit but because it
was irrelevant.
    The officers’ decision to hold open the door to the apart-
ment so that they could see into the living room while Thede
was getting dressed elsewhere in the apartment was simple
prudence and thus within the scope of the “exigent circum-
stances” (i.e., emergency) exception to the requirement of a
warrant. See, e.g., Kentucky v. King, 131 S. Ct. 1849, 1856–63
(2011). Even if she didn’t identify the “friend” in the apart-
ment as “News” (a question on which the evidence is in con-
flict), given the connection, evidenced by cellphone records,
between her and Cook’s accomplice, the “friend” in the
apartment could well be “BN” (that is, Cook)—a violent,
dangerous criminal, who might well be (though it turned
out that he wasn’t) armed and dangerous. Had the officers
waited for Thede to get dressed and open the door to the
apartment they might have found themselves six inches
from the barrel of a gun. As in protective-sweep cases, the
officers were justified in taking reasonable precautions to
minimize the danger to themselves. Maryland v. Buie, 494
U.S. 325, 333–35 (1990). Had they out of an abundance of
caution instead removed themselves from potential danger,
the suspect might have escaped. Compare Minnesota v. Ol-
son, 495 U.S. 91, 100–01 (1990).
   We thus needn’t decide whether, as the district court
found, Thede consented to the officers’ entry into her apart-
ment. Their opening the door (without entering) was pru-
dent given the potential danger that the “friend” might pose.
Once they saw him, they knew he was the suspect in the
6                                                 No. 14-1641


robbery that they were investigating, and it would be absurd
to think that they should have turned and left and applied
for a search warrant. Think of what might have ensued had
they been required to run off to get a search warrant before
they could lawfully enter the apartment and arrest Cook. As
soon as they left to get the warrant he would have split.
True, some of the four officers might have remained in the
hallway (while the others went to get a search warrant) and
followed Cook as he fled. But he might have shaken off the
tail, and still be at large today. Once he had left the apart-
ment and they recognized him as the robbery suspect, they
would have had probable cause to arrest him (or at the least
to stop him long enough to do a warrant check), and they
could have done this without a search warrant because the
hallway was a public space. But he might not have remained
there. He might have outrun them. Moreover, Thede’s
apartment was on the second floor; Cook could have jumped
out of a back window and fled without being seen by any of
the officers.
    Cook’s lawyer makes much of the fact that when the po-
lice saw Cook, Thede became upset and the police pulled her
into the hallway to prevent her from interfering with their
conversation with Cook. We can’t see the relevance of this
contretemps; Thede is not the plaintiff.
   Now suppose Thede and Cook had been co-owners or
co-occupants of the apartment and one or both of them had
objected to entry by the police, and in addition that there
had been no emergency justifying entry. Would that have
changed the outcome of this case? No. The warrant to arrest
Cook for violating parole is the key to this conclusion. The
Supreme Court said in Payton v. New York, 445 U.S. 573, 602–
No. 14-1641                                                       7


03 (1980), “that an arrest warrant requirement may afford
less protection than a search warrant requirement, but it will
suffice to interpose the magistrate’s determination of proba-
ble cause between the zealous officer and the citizen. If there
is sufficient evidence of a citizen’s participation in a felony to
persuade a judicial officer that his arrest is justified, it is con-
stitutionally reasonable to require him to open his doors to
the officers of the law. Thus, for Fourth Amendment pur-
poses, an arrest warrant founded on probable cause implicit-
ly carries with it the limited authority to enter a dwelling in
which the suspect lives when there is reason to believe the
suspect is within.” That was a dictum, but a considered ra-
ther than a casual one, and the lower courts including our
own have treated it as a rule. See, e.g., United States v. Jack-
son, 576 F.3d 465, 468–69 (7th Cir. 2009); United States v.
Thomas, 429 F.3d 282, 285–86 (D.C. Cir. 2005); United States v.
Hill, 649 F.3d 258, 262–64 (4th Cir. 2011); United States v. Har-
din, 539 F.3d 404, 423–24 (6th Cir. 2008).
    It’s true that the warrants involved in the Payton case
were for felonies, whereas the warrant in our case was for a
parole violation, which might not be a felony (the record is
silent on this point). But persons on parole have a dimin-
ished right of privacy, because parole is a form of custody,
and so an arrest warrant for violation of parole would entitle
officers to enter the parolee’s home to arrest him. United
States v. Pelletier, 469 F.3d 194, 200 (1st Cir. 2006); see also
United States v. Hollis, 780 F.3d 1064, 1068–69 (11th Cir. 2015);
United States v. Collins, 699 F.3d 1039, 1041–42 (8th Cir. 2012);
United States v. Thomas, supra, 429 F.3d at 285–86. Anyway
Cook was not a resident of Thede’s apartment, and obvious-
ly the subject of an arrest warrant has no greater expectation
of privacy if he is visiting someone rather than being at
8                                                   No. 14-1641


home. United States v. Jackson, supra, 576 F.3d at 467–68; see
also United States v. Underwood, 717 F.2d 482, 484 (9th Cir.
1983) (en banc).
     The arrest warrant was all that the police needed in order
to be justified in arresting Cook (setting to one side their jus-
tification based on an emergency situation). They didn’t
know there was a warrant for his arrest, however, and we
must consider whether that should matter. We think not,
though not because of the “collective knowledge” doctrine,
which allows an officer to stop, search, or arrest a suspect at
the direction of his superiors even if the officer lacks first-
hand knowledge of facts that would justify the action. See
United States v. Hensley, 469 U.S. 221, 232–33 (1985). The of-
ficers who arrested Cook had not been told to arrest him be-
cause of the warrant outstanding against him; had they been
told, they could have arrested him lawfully without know-
ing the basis on which the warrant had been issued. But
what they did in arresting Cook was exactly what they
would have done had they known about the warrant. They
did the right thing without knowing it was the right thing;
and since they did the right thing Cook has no valid objec-
tion.
    Suppose there are outstanding arrest warrants for two
persons, X and Y. One police officer has the warrant for X;
he doesn’t know there is a warrant outstanding for Y as well.
The officer arrests Y, mistakenly thinking that he is X. Is that
a false arrest? Or is it serendipity? It’s the latter, and should
not be punished by awarding damages to Y. Cf. Patton v.
Przybylski, 822 F.2d 697, 699–700 (7th Cir. 1987). Notice the
analogy to the “inevitable discovery” doctrine of Nix v. Wil-
No. 14-1641                                                    9


liams, 467 U.S. 431, 443–44 (1984); see United States v. Witzlib,
2015 WL 4664340, at *1–2 (7th Cir. Aug. 7, 2015).
   Officers who enter premises without reasonable belief
that they will find the person for whom they have a warrant
will still be liable when their quarry turns out not to be pre-
sent, and that should be sufficient to discourage officers
from entering homes when they have no basis to believe
they’ll find the suspect there. But that is beside the point of
the present case. The officers didn’t enter Thede’s apartment
until they saw Cook and thus knew they’d found their sus-
pect.
    All this to one side, there is no basis for any of the dam-
ages that Cook seeks; and damages are the only relief that he
does seek. “Probable cause to arrest is an absolute defense to
any claim under Section 1983 against police officers for
wrongful arrest.” Mustafa v. City of Chicago, 442 F.3d 544, 548
(7th Cir. 2006). And that is when there’s no warrant—here
there was one. Once Cook acknowledged to the officers that
his street names were “BN” and “Rex,” there was additional
probable cause to arrest him for the robbery. As for damages
for loss of personal property of Cook seized by the police
and not returned, that property was seized after Thede, fol-
lowing Cook’s arrest, had consented to a search of the
apartment. As it was her apartment, not Cook’s (he was not
a joint tenant), she had authority to consent. As for damages
for emotional distress caused by the entry of the police into
the apartment, there is no basis for thinking that the arrest
caused Cook more emotional distress than had the police
entered clutching the arrest warrant. Given Cook’s recent
commission of a violent robbery, moreover, it is hard to be-
lieve that the sight of police officers caused him emotional
10                                                   No. 14-1641


distress; he is not the sensitive plant of which Shelley wrote
in a poem of that name: “A Sensitive Plant in a garden
grew,/ And the young winds fed it with silver dew,/ And it
opened its fan-like leaves to the light,/ And closed them be-
neath the kisses of Night.”
    Nominal or punitive damages are out of the question,
too, given the arrest warrant. Any award of damages to
Cook arising out of the entry of the police into the apartment
that was not his would be a pure windfall. See Habitat Educa-
tion Center v. U.S. Forest Service, 607 F.3d 453, 460–61 (7th Cir.
2010); Hessel v. O’Hearn, 977 F.2d 299, 302–05 (7th Cir. 1992).
   The entry (if that is how peeking into the living room
should be described) was justified by the need to protect the
police officers from a possible assault by Cook; and at worst
the entry was a harmless error because of the existence of the
warrant and the absence of any possible entitlement to dam-
ages. The judgment for the defendants is therefore
                                                      AFFIRMED.
No. 14-1641                                                    11

    HAMILTON, Circuit Judge, concurring in the judgment. I
agree we must affirm the judgment. All members of the panel
agree we should affirm on a ground not briefed in this court:
there was a warrant for Cook’s arrest, which meant the offic-
ers’ entry was justified even though they did not know about
the warrant at the moment they entered Stacy Thede’s apart-
ment. See Payton v. New York, 445 U.S. 573, 602–03 (1980);
United States v. Jackson, 576 F.3d 465, 468–69 (7th Cir. 2009). On
other issues addressed in the majority opinion, however, my
views differ.
    After reviewing the original briefs filed while plaintiff
Cook was acting pro se, another panel of this court ordered
recruitment of counsel and briefing on two issues. The first
was the appropriate standard of review for the district court’s
decision to exclude Thede’s affidavit explaining that she did
not give her consent to the officers to enter her apartment. The
second was whether, if Thede’s affidavit is considered, the rec-
ord supports denial of defendants’ motion for summary judg-
ment, and we directed the parties to address the significance
of Gerald M. v. Conneely, 858 F.2d 378, 385 (7th Cir. 1988), and
cases following it. As requested, attorney Barack S. Echols and
his colleagues at Kirkland & Ellis have provided able repre-
sentation to Cook, for which the court is grateful.
   I agree we do not need to decide the standard-of-review
question here. Under any standard, I agree with the majority’s
conclusion that Thede’s affidavit was not a “sham” on the is-
sue of consent for the police to enter her apartment. Ante at 4.
Further explanation of that conclusion is needed, though.
   During Cook’s criminal trial, Thede had been asked just
one leading question on the issue of consent to enter:
12                                                    No. 14-1641

     Q Did the detectives come in the apartment?
     A Yes.
     Q You let them in?
     A Yes.
In her affidavit in this civil case, Thede explained that she had
meant that once the police officers had entered her apartment
without her consent, she did not tell them to leave and did not
object directly to their entry. She had not intended to give
them permission to enter. She had simply not objected after
they had entered without her permission. Thede testified in
her affidavit that she told the detectives she was willing to talk
with them in the hallway outside her door, that she closed the
door when she went back in the apartment to change clothes,
and that she never consented to allow them in.
    Merely answering the door does not give police consent to
enter a home. United States v. Sabo, 724 F.3d 891, 893 (7th Cir.
2013), citing Hadley v. Williams, 368 F.3d 747, 750 (7th Cir. 2004)
(genuine issue of fact on consent to enter home required re-
versal of summary judgment for officer on Fourth Amend-
ment claim); cf. United States v. Risner, 593 F.3d 692, 694–95
(7th Cir. 2010) (consent to enter implied when resident called
911 for emergency help). Closing the door was a clear signal
the officers did not have Thede’s consent to enter. Thede’s af-
fidavit is sufficient to distinguish this case from Gerald M., 858
F.2d at 385, and thus to defeat summary judgment on both the
merits and qualified immunity.
   It is also well established, however, that a witness cannot
create a genuine issue of material fact for purposes of sum-
mary judgment by contradicting her unequivocal prior testi-
mony, at least not without a good explanation. E.g., Adelman-
No. 14-1641                                                   13

Tremblay v. Jewel Cos., 859 F.2d 517, 520–21 (7th Cir. 1988).
Thede’s trial testimony that she “let” the officers in was not
unequivocal testimony, at least on the constitutional issue that
arises in this civil suit.
   To say that a person has “let” someone else enter her resi-
dence can cover a broad spectrum of actions and intentions. It
could mean that the resident warmly welcomed the visitor. It
could also mean only that the resident did not try to obstruct
physically an unwelcome visitor’s entry. Or it could mean
anything in between those two extremes.
   The consent needed to allow police to enter a residence
without a warrant lies along that continuum. The issue is
whether, in light of the totality of circumstances, the resident
indicated voluntary consent for the police to enter. See
Schneckloth v. Bustamonte, 412 U.S. 218, 227 (1973); Sabo, 724
F.3d at 893–94 (resident gave implied consent by answering
door and, in response to officer’s request to enter, stepping
back and to the side to allow officer to enter); United States v.
Risner, 593 F.3d 692, 694 (7th Cir. 2010).
    In Cook’s criminal trial, there was no effort to pin Thede
down to specific facts that would have placed her account at
a specific point on that continuum between a warm welcome
and coercion. That’s not surprising. Consent simply did not
matter in that trial. (In their own testimony in the criminal
trial, the officers did not even address the question of con-
sent.) Thede was thus entirely within her rights in explaining
in the affidavit what she had meant in her vague trial testi-
mony on the point.
   The sham doctrine must be applied with caution. It’s too
easy otherwise for a district court to start making credibility
14                                                         No. 14-1641

determinations as part of the summary judgment process:
“Few honest witnesses testify at any length without at least
occasional lapses of memory or needs for correction or clari-
fication.” Castro v. DeVry University, Inc., 786 F.3d 559, 571 (7th
Cir. 2015); accord, e.g., Bank of Illinois v. Allied Signal Safety Re-
straint Systems, 75 F.3d 1162, 1169–70 (7th Cir. 1996) (noting
need for caution: affidavit can be excluded as sham only
where witness has given “clear answers to unambiguous
questions which negate the existence of any genuine issue of
material fact”); Maldonado v. U.S. Bank, 186 F.3d 759, 769 (7th
Cir. 1999) (allowing defense witness’s affidavit to change dep-
osition testimony after witness consulted relevant records);
see also Moll v. Telesector Resources Group, Inc., 760 F.3d 198,
205–06 (2d Cir. 2014) (sham doctrine did not bar witness’s af-
fidavit explaining earlier testimony); Fed. R. Civ. P. 30(e) (de-
ponent must be allowed 30 days to review transcript and to
make changes in substance or form of testimony).
   Thede’s unexplained answer to one vague question in the
criminal trial is just the sort of testimony that can properly be
explained by a more detailed affidavit. The district court erred
by granting summary judgment on the theory that the officers
had consent to enter Thede’s apartment, and the majority does
not find otherwise. 1
    I respectfully disagree with the majority’s view that the of-
ficers were entitled to summary judgment on the theory that
exigent circumstances justified their entry into the apartment

     1The majority’s statement that Thede’s affidavit was “irrelevant,”
ante at 5, is difficult to square with the defendants’ motion for summary
judgment and the district court’s decision that we are reviewing. Both re-
lied exclusively on the issue of consent, based entirely on Thede’s ambig-
uous trial testimony.
No. 14-1641                                                   15

without either a warrant or consent. That theory was rejected
by the district court and was not briefed for our court. In fact,
the detectives had filed an earlier motion for summary judg-
ment based on exigent circumstances. The district court de-
nied that motion. See Cook v. O’Neill, No. 09-CV-87, Dkt. 55
(E.D. Wis. March 7, 2011).
    The officers’ actions were not consistent with a theory of
exigent circumstances. Defendant Baldwin testified that
Thede told them someone named “News” (a version of Cook’s
nicknames, “Bad News” or “BN”) was in the apartment, so
that Baldwin was immediately concerned for the safety of the
officers and the public. Baldwin’s account is disputed, though,
and other evidence shows that the officers then allowed
Thede to return to the apartment to change her clothes.
    That is not the response of officers who believe that exi-
gent circumstances justify immediate entry to deal with an
imminent threat to officer safety. Nor was there any indication
that Thede or anyone else was in danger or that evidence was
about to be destroyed. See Kentucky v. King, 563 U.S. 452, —,
131 S. Ct. 1849, 1856–57 (2011) (summarizing exigent circum-
stances exception); Hawkins v. Mitchell, 756 F.3d 983, 993 (7th
Cir. 2014) (rejecting exigent circumstance rationale as a matter
of law even where officers “arrived at a disorderly scene” and
suspect was known to “get[] violent sometimes”).
    Unjustified entry into a home is the “chief evil” against
which the Fourth Amendment was directed, Sabo, 724 F.3d at
893, quoting Payton v. New York, 445 U.S. 573, 585 (1980), so
the bar for exigent circumstances is higher than what was
shown by the undisputed evidence here. See, e.g., United
States v. Venters, 539 F.3d 801, 807–09 (7th Cir. 2008) (warrant-
less entry justified where officers knew that children had been
16                                                   No. 14-1641

in house for several days where adults were manufacturing
methamphetamine, posing great risk to bystanders, but court
emphasized narrowness of exigent circumstances finding). In
my view, the district court was correct to deny summary judg-
ment on a theory of exigent circumstances. The majority errs
by reversing that determination and stretching the concept
too far, especially without briefing and argument on the the-
ory.
    In the end, however, I agree we must affirm summary
judgment for the defendants. If the facts were as plaintiff con-
tends, the officers were lucky. It turned out there was already
an active warrant for plaintiff’s arrest for a parole violation,
even though the defendant officers did not know about it. See
United States v. Jackson, 576 F.3d 465, 468 (7th Cir. 2009). I see
no reason not to give the officer-defendants the benefit of the
Jackson approach despite their lack of knowledge. If Thede
herself, on the other hand, were asserting a Fourth Amend-
ment claim, on this record she would be entitled to a jury trial.
