In the

United States Court of Appeals

For the Seventh Circuit ____________________

No. 15-3044

MARCUS MUHAMMAD, et al.,

Plaintiffs-Appellants,

v.

DEL PEARSON, Police Officer #16462,

Defendant-Appellee.

____________________

Appeal from the United States District Court for the

Northern District of Illinois, Eastern Division.

No. 13-CV-1122 — Charles R. Norgle, Judge.

____________________

ARGUED NOVEMBER 8, 2017 — DECIDED AUGUST 17, 2018

____________________

Before WOOD, Chief Judge, and FLAUM and HAMILTON, Circuit Judges.

HAMILTON, Circuit Judge. When Officer Del Pearson and 

other Chicago police officers executed a search warrant for 

“apartment 1” at a Chicago address, there was a problem with 

the warrant. Apartment 1 did not exist. The building contained an apartment 1A and an apartment 1B. Pearson and the 

other officers actually searched apartment 1A. They did not 

find the drugs and related items they were seeking.
2 No. 15-3044

The occupants of apartment 1A then filed this suit against 

Officer Pearson under 42 U.S.C. § 1983 for violating their 

Fourth Amendment rights through unlawful entry and false 

arrest. Both sides moved for summary judgment. The district 

court denied plaintiffs’ motion and granted Pearson’s. We affirm the judgment but on narrow grounds. Law enforcement 

officers who discover that a search warrant does not clearly 

specify the premises to be searched must ordinarily stop and 

clear up the ambiguity before they conduct or continue the 

search. See Maryland v. Garrison, 480 U.S. 79, 86 (1987); United 

States v. Kelly, 772 F.3d 1072, 1083 (7th Cir. 2014). If they do 

not, they may lose the legal protection the warrant provides 

for an invasion of privacy and accompanying restraints on liberty.

As we explain below, however, we conclude that summary judgment for the officer was appropriate here. Defendant Pearson testified that he did not know there were two 

apartments, including an apartment 1B, and he has offered 

undisputed, reliable, and contemporaneous documents confirming his after-the-fact testimony that the address searched 

was in fact the correct target of the search authorized by the 

ambiguous warrant. Summary judgment on the unlawful entry claims was correct. Also, Officer Pearson had arguable 

probable cause to arrest plaintiff Muhammad for suspected 

drug trafficking, though Pearson quickly confirmed that Muhammad was not the right suspect and released him within 

fifteen minutes. Summary judgment based on qualified immunity was also correct on that unlawful arrest claim. 

I. Factual and Procedural Background

Our account of the facts applies the summary judgment 

standard, relying on facts that are not genuinely disputed but 
No. 15-3044 3

giving plaintiffs, as the non-moving parties, the benefit of conflicts in the evidence and reasonable inferences from the evidence. Zimmerman v. Doran, 807 F.3d 178, 182 (7th Cir. 2015), 

citing Hardaway v. Meyerhoff, 734 F.3d 740, 743 (7th Cir. 2013).

Pearson applied for the warrant based on a tip from a 

known and previously reliable informant. The affidavit for 

the warrant included the following information. In the three 

months leading up to the tip, Pearson’s source had provided 

information leading to three felony arrests and seizures of illegal drugs. The source told Pearson that she bought drugs 

from a man named “Moe Moe” at “3236 E. 92nd St Apt#1.” 

She described Moe Moe as a black male who was 25 to 30 

years old, approximately 5’8” tall and medium build. Pearson 

checked Chicago Police Department databases and discovered that a man named Jamison Carr “used the address of 

3236 E. 92nd St. on a previous arrest.” The affidavit did not 

indicate which apartment number was associated with that 

arrest record. The source identified a photograph of Carr as 

“Moe Moe.”

The affidavit also provided details about the transaction. 

It said that the source met with Carr in apartment 1. He led 

her into a back bedroom where she saw a “large frame semiauto blue steel handgun” on the table and purchased “four 

small knotted baggies of crack cocaine.” The affidavit also 

stated that Officer Pearson and the source “personally drove 

by the 3200 block of E. 92nd St” and that the source “pointed 

to the apartment at 3236 E 92nd St. and identified it as the 

apartment where [she] met the individual Jamison Carr a/k/a 

‘Moe Moe’ and purchased the crack cocaine and observed the 

above handgun.”
4 No. 15-3044

Based on that affidavit, a state court judge issued a search 

warrant—which Pearson also drafted—for “Jamison Carr, 

a/k/a ‘Moe Moe’, a male black, 28 yoa, 5’08” tall, 140 lbs, medium build, black hair,IR#1300675” and for premises described as “a multi-unit building located at 3236 E. 92nd St. 

Apt#1, Chicago, Illinois Cook County.” The search warrant 

authorized the seizure of weapons, cocaine, drug paraphernalia, money and drug transaction records, and proof of residency as evidence of the crimes of unlawful use of a weapon 

by a felon and drug possession.

In his deposition, Officer Pearson provided more detail 

about his investigation leading up to the warrant. He compiled an array of photographs from police databases of people 

associated with the 92nd Street address and showed them to 

the source. (The photo array is not in the record. Pearson testified he kept the file at his home and “probably” threw it 

away.) The source identified Jamison Carr as “Moe Moe.” She 

also identified Tracy Jones from a photograph and said Jones 

lived in the target apartment with her pregnant daughter and 

her daughter’s boyfriend, who sold crack cocaine from their 

bedroom, where there was a gun.

Turning to the contemporaneous documents indicating 

that apartment 1A was the correct, intended target of the 

search authorized by the warrant, Officer Pearson testified 

that before he drafted the warrant affidavit, he ran the license 

plate on Tracy Jones’s car through the LEADS database. He 

learned that the car was registered to Tracy Jones in apartment 1A. The report linking Jones’s car to apartment 1A is 

dated March 21, 2011—the day before the warrant was issued 

and executed and, according to the affidavit, the same day as 

Pearson’s meeting with the source. Pearson also filled out a 
No. 15-3044 5

“deconfliction submission.” (Chicago police officers use this 

document and procedure before executing search warrants to 

ensure that other local or federal law-enforcement agencies 

are not investigating the same address.) The deconfliction 

submission is dated March 22, 2011, the date the warrant was 

executed. It lists apartment 1A as the residential address of

Jamison Carr as the “target.” When Pearson executed the warrant, he had both the LEADS report for Jones’s car and the 

deconfliction submission with him.

A team of fourteen Chicago police officers executed the 

search warrant late in the evening of March 22, 2011. They 

pounded on the rear door of apartment 1A, said they were the 

police, but received no response. Pearson was with a group of 

officers who used a battering ram to try to break down the 

rear door of apartment 1A. Another group of officers was stationed at the front door.

Inside apartment 1A, the officers found plaintiff Marcus 

Muhammad in the bedroom with plaintiff Micheala Jones, 

who was pregnant. The officers did not find a gun and did not 

find any drugs. The officers reported that they found ammunition in the bedroom, but plaintiffs submitted affidavits stating that they did not own, possess, or have any knowledge of 

the ammunition. Plaintiffs claim the officers planted it. 

Officer Pearson noticed that Muhammad did not look like 

the picture of Jamison Carr but testified that he “wasn’t sure.” 

Muhammad denied that his nickname was Moe Moe, but he 

did not have any identification showing his correct name or 

address (and that he was not Carr). Muhammad was seven 

years younger and three inches shorter than Carr. Pearson arrested Muhammad and took him to the station but released 
6 No. 15-3044

him after about 15 minutes, once he confirmed that Muhammad was not Carr. That arrest is the basis of Muhammad’s 

false arrest claim.

The district court granted summary judgment for Officer 

Pearson on all claims. It held that Pearson was entitled to qualified immunity on the unlawful entry claims because plaintiffs failed to show a violation of clearly established law. The 

court granted summary judgment for Pearson on Muhammad’s false arrest claim, finding that Pearson had probable 

cause to arrest him for possessing ammunition without a firearm owner’s identification card. The district court dismissed 

the other plaintiffs’ false arrest claims because they had failed 

to show that officers detained them beyond what was permissible in executing the warrant.

II. Analysis

For civil damages claims under 42 U.S.C. § 1983 for violations of constitutional rights, the doctrine of qualified immunity “shields officials from civil liability so long as their conduct 

‘does not violate clearly established statutory or constitutional rights of which a reasonable person would have 

known.’” Mullenix v. Luna, 136 S. Ct. 305, 308 (2015) (per curiam), quoting Pearson v. Callahan, 555 U.S. 223, 231 (2009). 

“Put simply, qualified immunity protects ‘all but the plainly 

incompetent or those who knowingly violate the law.’” Id., 

quoting Malley v. Briggs, 475 U.S. 335, 341 (1986). 

“To overcome a defendant’s invocation of qualified immunity, a plaintiff must show: ‘(1) that the official violated a 

statutory or constitutional right, and (2) that the right was 

‘clearly established’ at the time of the challenged conduct.’” 

Green v. Newport, 868 F.3d 629, 633 (7th Cir. 2017), quoting 
No. 15-3044 7

Ashcroft v. al-Kidd, 563 U.S. 731, 735 (2011). We have discretion 

to decide which element of the qualified immunity defense to 

address first. Pearson, 555 U.S. at 236. If the answer to either 

question is no, the defendant official is entitled to qualified 

immunity. Gibbs v. Lomas, 755 F.3d 529, 537 (7th Cir. 2014). We 

address first the plaintiffs’ claims for unlawful entry and then 

their claims for false arrest.

A. Unlawful Entry Claims

Under the Fourth Amendment, a search warrant must 

“particularly describ[e] the place to be searched.” Failure to 

do so renders the warrant a “general warrant,” which the 

amendment clearly forbids. See Payton v. New York, 445 U.S. 

573, 584 n.21 (1980) (tracing roots of particularity requirement 

to colonists’ objections to writs of assistance). The particularity requirement is satisfied if “the description is such that the 

officer with a search warrant can with reasonable effort ascertain and identify the place intended.” Steele v. United States, 

267 U.S. 498, 503 (1925).

In this case, a judge found probable cause to search the 

apartment where the informant told Officer Pearson she had 

bought cocaine from “Moe Moe,” who had a gun at the time. 

The problem is that the warrant authorized a search of “apartment 1,” while the actual building had an apartment 1A and 

an apartment 1B, but no apartment 1.

Warrants with similar errors or ambiguities are not new. 

When the police go forward with a search without checking 

back with the issuing judge, litigation is likely. Sometimes 

there is just a mistake in the papers. In other cases, officers 

seeking search warrants cannot obtain accurate information 

(especially about the interiors of multi-unit buildings), at least 
8 No. 15-3044

not without alerting the targets of the investigation. See, e.g., 

Maryland v. Garrison, 480 U.S. 79, 80 (1987) (warrant was for 

“third floor apartment” but third floor had two apartments); 

United States v. McMillian, 786 F.3d 630, 634 (7th Cir. 2015) (typographical error in warrant and affidavit where target street 

address for search was “6333” but detective typed “6633”); 

United States v. Kelly, 772 F.3d 1072, 1076 (7th Cir. 2014) (warrant for “upper apartment” but building did not have upper 

and lower apartments and was instead “bisected into front 

and rear multi-story units”). And sometimes information is 

lost in communications between two police officers. E.g., Jones 

v. Wilhelm, 425 F.3d 455, 459 (7th Cir. 2005) (one officer obtained warrant for “upstairs apartment on the right,” but executing officer realized that phrase described two apartments 

because building had two staircases on opposite sides of 

building).

Officers executing warrants like these may violate the 

Fourth Amendment if they know or should know, before execution, that the warrant has an error or critical ambiguity 

that risks a search of the wrong location. Garrison, 480 U.S. at 

86. At the same time, typographical errors or other mistakes 

will “not invalidate a warrant if the affidavit otherwise identifies the targeted premises in sufficient detail and there is no 

chance that another location might be searched by mistake.” 

McMillian, 786 F.3d at 640, citing Kelly, 772 F.3d at 1081. 

We approach this illegal entry claim through the lens of 

qualified immunity and ask whether Officer Pearson’s actions 

violated clearly established law. More precisely, since the district court granted summary judgment for Pearson, the question is whether the undisputed facts show that Pearson did 

not violate clearly established law. “The Supreme Court has 
No. 15-3044 9

instructed that ‘clearly established law should not be defined 

at a high level of generality.’” Green, 868 F.3d at 633, quoting 

White v. Pauly, 137 S. Ct. 548, 552 (2017) (per curiam). “While 

a case directly on point is not required, ‘the clearly established 

law must be particularized to the facts of the case.’” Id., quoting White, 137 S. Ct. at 551 (internal quotation marks omitted). 

“[G]eneral statements of the law” can give officers “fair and 

clear warning.” White, 137 S. Ct. at 552, quoting United States 

v. Lanier, 520 U.S. 259, 271 (1997). But “in the light of pre-existing law the unlawfulness must be apparent.” Id., quoting 

Anderson v. Creighton, 483 U.S. 635, 640 (1987); see also District 

of Columbia v. Wesby, 138 S. Ct. 577, 590 (2018) (“Of course, 

there can be the rare ‘obvious case,’ where the unlawfulness 

of the officer’s conduct is sufficiently clear even though existing precedent does not address similar circumstances.”), 

quoting Brosseau v. Haugen, 543 U.S. 194, 199 (2004) (per curiam); Hope v. Pelzer, 536 U.S. 730, 741 (2002) (denying qualified immunity because handcuffing prisoner to hitching post 

for hours in summer sun violated clearly established law and 

noting that “officials can still be on notice that their conduct 

violates established law even in novel factual circumstances”).

With that qualified immunity standard in mind, we take a 

closer look at Fourth Amendment law where search warrants 

have errors or key ambiguities. We have held that officers executing a search warrant can rely on what they know and see 

independent of the documents to make sure they search the 

correct premises, at least where the circumstances show there 

is no reasonable chance that the officers will search the wrong 

location, meaning a location other than the one the issuing 

magistrate authorized. E.g., McMillian, 786 F.3d at 640; Kelly, 

772 F.3d at 1081; United States v. Johnson, 26 F.3d 669, 688 n.14, 
10 No. 15-3044

692 (7th Cir. 1994). As McMillian makes clear, other circuits 

have long agreed. See, e.g., United States v. Gahagan, 865 F.2d 

1490, 1497–98 (6th Cir. 1989) (collecting cases and affirming 

denial of motion to suppress); United States v. Garza, 980 F.2d 

546, 552 (9th Cir. 1992); United States v. Burke, 784 F.2d 1090, 

1092–93 (11th Cir. 1986) (reversing grant of motion to suppress; despite mistakes in address in warrant, executing officers knew enough to know which premises should be 

searched); United States v. Turner, 770 F.2d 1508, 1511 (9th Cir. 

1985) (affirming denial of motion to suppress; despite mistaken house number in warrant, executing officers could rely 

on their knowledge to search correct premises).

The plaintiffs rely heavily on Jones v. Wilhelm, where we 

reversed a grant of qualified immunity for an officer who executed an ambiguous warrant despite knowing that its description of the place to be searched described two different 

apartments. 425 F.3d at 462–63 (officer knew, based on prior 

surveillance, that building contained two staircases on opposite sides of building, rendering description of the “upstairs 

apartment on the right” ambiguous). We wrote in Jones that 

the Fourth Amendment prohibited the officer “from applying 

his earlier surveillance and subsequent deductions to resolve 

the warrant’s ambiguity rather than presenting those observations to a magistrate for determination.” Id. at 463.

Our opinion in Jones recounted the police mistakes in that 

case. One officer received a tip from an informant that a 

named person in a second-floor apartment was manufacturing methamphetamine. That officer obtained a warrant to 

search not the named person’s apartment but “the upstairs 

apartment on the right.” He then gave that warrant to another 

officer who had been watching pedestrian traffic to the second 
No. 15-3044 11

floor of the building. That officer, defendant Wilhelm in the 

case, did not go back to the issuing court (and the officer who 

had developed the probable cause information) to clear up the 

ambiguity before carrying out the search. Instead, he seems to 

have made his best guess about whether “the upstairs apartment on the right” was to be chosen from the viewpoint of the 

front door or the rear door. He chose wrongly and searched 

the apartment that had not been the subject of the informant’s 

tip. 425 F.3d at 463–64.

Search first, check later, is not a sound policing strategy. 

Jones teaches that officers need to read the warrant before executing it, and they should call a judge if there is a discrepancy between the affidavit and the warrant. See, e.g., McMillian, 786 F.3d at 634 (officer on scene called judge after noticing error in address listed on warrant and affidavit). If they 

do not, they risk both personal civil liability and suppression 

of evidence in any criminal prosecution.

This case, however, is different from Jones in a critical way. 

Unlike the officer in Jones, who knew there were two apartments, knew that the warrant was ambiguous, and essentially 

took his best guess about which one to search, Officer Pearson 

testified that when he applied for the warrant he did not know 

there was an apartment 1B in the building. He also testified 

that the omission of “A” from the warrant was a clerical omission. Pearson used his knowledge of the case, including information from his source, to search the correct apartment, the 

one for which he had probable cause.

So Officer Pearson relies on the line of cases cited above 

that allow executing officers to rely on what they know to 

make sure they search the correct locations, despite errors or 

ambiguities in search warrants. The critical question for this 
12 No. 15-3044

case is whether it was proper to resolve Pearson’s defense in 

his favor on summary judgment. In civil litigation about 

searches that turned out to involve mistakes or ambiguities in 

warrants, there can be plenty of room for material factual disputes about what the executing officers actually knew and 

did. Parties and courts can reasonably question the credibility 

of officers’ after-the-fact attempts to explain away their mistakes. Such cases may well present factual issues that require 

a full trial to resolve.

In this case, however, summary judgment was justified. 

Officer Pearson has offered undisputed evidence, in the form 

of reliable, contemporaneous documents, confirming that the 

correct target apartment—the one he intended to search and 

had probable cause to search—was apartment 1A. The 

LEADS report (dated the day before the warrant) and the deconfliction submission (dated the same day the warrant was 

executed) both listed apartment “1A” as the target of the 

search. Those documents remove reasonable grounds for disputing Pearson’s claim that he used his knowledge to ensure 

that he searched the intended location.

This contemporaneous evidence distinguishes this case 

from others where we held that officers could not have concluded that a plaintiff’s apartment was the appropriate target 

of the search warrant. E.g., Jacobs v. City of Chicago, 215 F.3d 

758, 767–71 (7th Cir. 2000) (reversing grant of defendant’s motion to dismiss and denying qualified immunity where reasonable officer could not have concluded plaintiff’s apartment 

was target of search and where there was “no indication that 

the officers were certain that plaintiffs’ apartment was the 

proper subject of the search”; warrant was for entire building 
No. 15-3044 13

but building actually consisted of three apartments with separate entrances).

The reliable, contemporaneous documents avoid the disputes and concerns that arise when “an executing officer is the 

sole source of information about the location of the premises 

to be searched.” See United States v. Lora-Solano, 330 F.3d 1288, 

1294 (10th Cir. 2003). The documents confirm that here there 

was no substantial risk of searching by mistake someplace 

other than the target. As in Kelly, that risk was further reduced 

by the fact that only one apartment was accessible from the 

rear door that Pearson entered. See Kelly, 772 F.3d at 1083 

(“The officers limited their search to the targeted apartment 

and, because only one apartment was accessible from the door 

through which they entered the building, there was no risk 

that they might inadvertently have searched the wrong unit.”) 

(footnote omitted). That distinction means that, in these limited circumstances, Officer Pearson is entitled to qualified immunity on summary judgment. 

The contemporaneous documents make Pearson’s qualified-immunity defense stronger than the officer’s in Jones. 

They objectively indicate that Officer Pearson “did not choose 

to search plaintiffs’ apartment at random or maintain willful 

ignorance of which apartment” to search, Jones, 425 F.3d at 

470 (Flaum, J., concurring in part and dissenting in part) (internal quotation marks omitted), and in the language of the 

Jones majority, Pearson did not realize there were two apartments and try to use his observations to make his best guess 

about which was the correct target, see id. at 465–66. In this 

case, the documents provide contemporaneous support for 

Pearson’s testimony that he searched the apartment to which 
14 No. 15-3044

the source pointed and for which the issuing judge had found 

probable cause. 

Given the case law that allows an executing officer to use

his or her own knowledge to resolve ambiguities, at least 

where there is no chance that the wrong location might be 

searched by mistake, see McMillian, 786 F.3d at 640, citing 

Kelly, 772 F.3d at 1081, and the contemporaneous documentation that corroborates Pearson’s testimony, we affirm the district court’s grant of summary judgment. Plaintiffs have not 

identified a precedent that should have alerted Officer Pearson that he could not proceed to search the apartment that he 

knew, beyond reasonable dispute, was the intended target. 

See, e.g., Abbott v. Sangamon County, 705 F.3d 706, 723–24 (7th 

Cir. 2013), citing Wheeler v. Lawson, 539 F.3d 629, 639 (7th Cir. 

2008). On that ground, we affirm summary judgment for 

Pearson on the entry claims based on qualified immunity. 

B. False Arrest Claims

Plaintiffs base their false arrest claims on two theories. 

Tracy, Terrance, and Micheala Jones claim that they were detained while the police were executing an invalid search warrant. Their claims fail for the same reasons Pearson is entitled 

to qualified immunity on the unlawful entry claim, which was 

also based on the challenge to the validity of the search warrant. When police are executing a search warrant, the Fourth 

Amendment does not forbid them from detaining the occupants of the premises during the search. See Muehler v. Mena, 

544 U.S. 93, 98–100 (2005) (vacating and remanding denial of 

qualified immunity), citing Michigan v. Summers, 452 U.S. 692, 

705 (1981).
No. 15-3044 15

Muhammad’s claim is different. He was actually arrested 

and taken to the police station after the search was completed. 

He was released after fifteen minutes.

“Probable cause is an absolute bar to a claim of false arrest 

asserted under the Fourth Amendment and section 1983.” 

Stokes v. Board of Education of City of Chicago, 599 F.3d 617, 622 

(7th Cir. 2010), citing McBride v. Grice, 576 F.3d 703, 707 (7th 

Cir. 2009) (affirming summary judgment for defendant police 

officer). “Probable cause exists if, at the time of the arrest, the 

facts and circumstances within the defendant’s knowledge 

‘are sufficient to warrant a prudent person, or one of reasonable caution, in believing, in the circumstances shown, that 

the suspect has committed ... an offense.’” Id., quoting Chelios 

v. Heavener, 520 F.3d 678, 686 (7th Cir. 2008) (reversing summary judgment for arresting officer).

The probable-cause standard is objective and “relies on 

the common-sense judgment of the officers based on the totality of the circumstances.” Jackson v. Parker, 627 F.3d 634, 638 

(7th Cir. 2010), quoting United States v. Reed, 443 F.3d 600, 603 

(7th Cir. 2006). Probable cause “deals with probabilities and 

depends on the totality of the circumstances.” Wesby, 138 S. 

Ct. at 586, quoting Maryland v. Pringle, 540 U.S. 366, 371 (2003). 

Probable cause “is ‘a fluid concept’ that is ‘not readily, or even 

usefully, reduced to a neat set of legal rules,’” id., quoting Illinois v. Gates, 462 U.S. 213, 232 (1983). “It ‘requires only a probability or substantial chance of criminal activity, not an actual 

showing of such activity.’” Id., quoting Gates, 462 U.S. at 243, 

n.13.

The district court granted summary judgment on the theory that Pearson had probable cause to arrest Muhammad for 
16 No. 15-3044

possessing ammunition without a firearm owner’s identification card, a violation of 430 ILCS 65/2(a)(2). That was incorrect, at least on a motion for summary judgment. Plaintiffs 

designated evidence that creates a genuine fact issue as to 

whether the police planted the ammunition. Pearson testified 

that the officers found bullets in Micheala’s bedroom, but 

plaintiffs filed affidavits testifying that they did not own, possess, or have any personal knowledge of the ammunition the 

officers claim to have found in the apartment. That conflicting 

evidence presents a factual dispute that cannot be resolved on 

a motion for summary judgment.

Nevertheless, Officer Pearson had arguable probable 

cause to arrest Muhammad for the drug offense associated 

with the source’s tip. An arrest is constitutional if it is made 

with probable cause for an offense, even if the arresting officer’s stated or subjective reason for the arrest was for a different offense. See Devenpeck v. Alford, 543 U.S. 146, 153 (2004). 

Qualified immunity is available if there is “arguable probable 

cause” for the arrest. See Hunter v. Bryant, 502 U.S. 224, 227–

28 (1991) (reversing denial of qualified immunity); Humphrey 

v. Taszak, 148 F.3d 719, 725 (7th Cir. 1998) (same).

Officer Pearson had arguable probable cause to arrest Muhammad for possessing cocaine with intent to deliver, a violation of 720 ILCS 570/401, even though he turned out to be 

the wrong person. The undisputed facts show the following. 

Before entering apartment 1A, Pearson had probable cause to 

believe that a black male named Jamison Carr had been selling drugs from the apartment, that the man had a firearm he 

kept visible for drug deals, and that the man in question had 

a pregnant girlfriend. (The detail about the pregnant girlfriend is from Pearson’s deposition, not the complaint for the 
No. 15-3044 17

search warrant, but we see no basis for a genuine dispute 

about the point.) Upon entering the apartment, Pearson encountered in the bedroom a black male with a pregnant girlfriend. That man denied that his nickname was “Moe Moe” 

and denied that he was Carr, but he did not have identification to prove who he was or where he lived. Muhammad was 

a few years younger and about three inches shorter than Carr. 

While on the scene in the apartment, Pearson thought Muhammad did not look like the picture of Carr that he had, but 

testified that he “wasn’t sure.”

This information was not enough to convict Muhammad, 

of course, but a reasonable officer in Pearson’s situation could 

have found that he had probable cause to arrest Muhammad, 

at least long enough to figure out definitively whether he was 

the right person or not. Under these circumstances, especially 

where Muhammad had no identification with him, a reasonable officer could have suspected that Muhammad might be 

lying about his identity. See generally Wesby, 138 S. Ct. at 587 

(reasonable for officers investigating unlawful entry to infer 

partygoers lied because they claimed to be attending a bachelor party but could not identify the bachelor or who had invited them), citing Devenpeck, 543 U.S. at 149, 155–56; see also 

Hill v. California, 401 U.S. 797, 803 (1971) (“aliases and false 

identifications are not uncommon”). That uncertainty about 

Muhammad’s identity points toward qualified immunity.

A reasonable officer can have probable cause even if she 

turns out to be mistaken, Stokes, 599 F.3d at 622, citing Chelios 

v. Heavener, 520 F.3d 678, 686 (7th Cir. 2008), and Kelley v. 

Myler, 149 F.3d 641, 646 (7th Cir. 1998), and even if a witness 

misidentifies the target, Gramenos, 797 F.2d at 439 (“Probable 

cause does not depend on the witness turning out to have 
18 No. 15-3044

been right; it’s what the police know, not whether they know 

the truth, that matters.”). Discrepancies between a witness’s 

description and an officer’s observation of the suspect are not 

unusual and do not automatically negate probable cause. See 

Pasiewicz v. Lake County Forest Preserve District, 270 F.3d 520, 

524 (7th Cir. 2001) (officers had probable cause to arrest man 

who did not exactly match witnesses’ description but “bore a 

fair resemblance”). The Fourth Amendment “demands reasonableness, not perfection.” Id. at 525.

Plaintiffs point out that Officer Pearson based Muhammad’s arrest on some facts about the informant’s tip that do 

not appear in the affidavit for the search warrant. Affidavits 

for warrants are not required to include all facts known to the 

officer, and the focus of the affidavit was the search, not the 

arrest of Carr. Muhammad has not presented a genuine issue 

of material fact disputing Pearson’s deposition testimony 

about the informant’s information about the pregnant girlfriend or Pearson’s uncertainty about Muhammad’s identity 

and residence. Accordingly, Officer Pearson had at least arguable probable cause to arrest Muhammad and is entitled to 

qualified immunity for his arrest.

The judgment of the district court is

AFFIRMED.