PEOPLE v FREDERICK

PEOPLE v VAN DOORNE

Docket Nos. 153115 and 153117. Argued on application for leave to appeal March 9, 

2017. Decided June 1, 2017. 

Michael Frederick and Todd Van Doorne were separately charged in the Kent Circuit 

Court with various drug offenses after seven officers from the Kent Area Narcotics Enforcement 

Team made unscheduled visits to the defendants’ respective homes during the predawn hours on 

March 18, 2014. Officers knocked on Frederick’s door around 4:00 a.m. and on Van Doorne’s 

door around 5:30 a.m. Officers woke defendants and their families for the purpose of

questioning each defendant about marijuana butter that they suspected the defendants possessed. 

Both defendants subsequently consented to a search of their respective homes, and marijuana

butter and other marijuana products were recovered from each home. Defendants moved to 

suppress the evidence, and the court, Dennis B. Leiber, J., denied both motions, concluding that 

the officers had not conducted a search by knocking on defendants’ doors during the predawn 

hours and that the subsequent consent searches were valid. Defendants sought interlocutory 

leave to appeal, which the Court of Appeals denied in separate unpublished orders, entered 

October 15, 2014 (Docket Nos. 323642 and 323643). Defendants sought leave to appeal in the

Supreme Court. The Supreme Court, in lieu of granting leave to appeal, remanded the cases to 

the Court of Appeals for consideration as on leave granted and directed the Court of Appeals to 

address whether the “knock and talk” procedure conducted in these cases was consistent with the 

Fourth Amendment as articulated in Florida v Jardines, 569 US ___; 133 S Ct 1409 (2013). 

People v Frederick, 497 Mich 993 (2015); People v Van Doorne, 497 Mich 993 (2015). The 

Court of Appeals consolidated the two cases and issued a split opinion. 313 Mich App 457 

(2015). The majority concluded that the officers’ predawn “knock and talk” visits were within 

the scope of the public’s implied license because homeowners would be unsurprised to find a 

predawn visitor delivering a newspaper or seeking emergency assistance, but the dissenting 

judge concluded that the police conduct violated the Fourth Amendment because the searches, 

which occurred during hours at which a homeowner would not expect visitors, were outside the 

scope of a proper knock and talk procedure. Defendants sought leave to appeal, and the Supreme 

Court ordered and heard oral argument on whether to grant the application or take other action. 

499 Mich 952 (2016). 

In a unanimous opinion by Justice MCCORMACK, in lieu of granting leave to appeal, the 

Supreme Court held:

Michigan Supreme Court

Lansing, Michigan

Syllabus Chief Justice:

Stephen J. Markman

Justices:

Brian K. Zahra

Bridget M. McCormack

David F. Viviano

Richard H. Bernstein

Joan L. Larsen

Kurtis T. Wilder

This syllabus constitutes no part of the opinion of the Court but has been 

prepared by the Reporter of Decisions for the convenience of the reader.

Reporter of Decisions:

Kathryn L. Loomis
The scope of the implied license to approach a house and knock is time-sensitive; it 

generally does not extend to predawn approaches. While approaching a home with the purpose 

of gathering information is not, standing alone, a Fourth Amendment search, when informationgathering is conjoined with a trespass, a Fourth Amendment search has occurred. In these cases, 

the police conduct exceeded the scope of the implied license to knock and talk because the 

officers approached the defendants’ respective homes during the predawn hours; therefore, the 

officers trespassed on Fourth-Amendment-protected property. And because the officers 

trespassed while seeking information, they performed searches in violation of the Fourth 

Amendment.

1. The proper scope of a knock and talk is determined by the implied license that is 

granted to the general public. Therefore, a police officer not armed with a warrant may approach 

a home and knock precisely because that is no more than any private citizen might do. When 

police officers stray beyond what any private citizen might do, they have strayed beyond the 

bounds of a permissible knock and talk; in other words, the officers are trespassing. Just as there 

is no implied license to bring a drug-sniffing dog to someone’s front porch, there is generally no 

implied license to knock at someone’s door in the middle of the night. Background social norms 

that invite a visitor to the front door typically do not extend to a visit in the middle of the night. 

Accordingly, the scope of the implied license to approach a house and knock is time-sensitive; it 

generally does not extend to predawn approaches. Additionally, while approaching a home with 

the purpose of gathering information is not, standing alone, a Fourth Amendment search, when 

information-gathering is conjoined with a trespass, a Fourth Amendment search has occurred. In 

these cases, the police officers exceeded the scope of the implied license to knock and talk 

because the officers approached defendants’ respective homes without warrants during the 

predawn hours; therefore, the officers trespassed on Fourth-Amendment-protected property. 

And because the officers trespassed while seeking information about defendants’ alleged 

possession of marijuana butter, they performed searches in violation of the Fourth Amendment.

2. Consent searches, when voluntary, are an exception to the warrant requirement. The 

voluntariness question turns on whether a reasonable person would, under the totality of the 

circumstances, feel able to choose whether to consent. Evidence obtained through an illegal 

search or seizure is tainted by that initial illegality unless sufficiently attenuated from it. Thus, 

even when consent is voluntary, if it is not attenuated from the unconstitutional search, the 

evidence must be suppressed. Three factors are considered in determining whether consent is 

sufficiently attenuated: (1) the temporal proximity of the illegal act and the alleged consent, (2) 

the presence of intervening circumstances, and (3) the purpose and flagrancy of the official 

misconduct. In these cases, because the trial court determined that there was no Fourth 

Amendment violation, it did not consider whether the subsequent consent was attenuated from 

the illegality. Therefore, the cases had to be remanded to the trial court for consideration of that 

question in the first instance.

Reversed and remanded to the Kent Circuit Court to determine whether defendants’ 

consent to search was attenuated from the officers’ illegal search.

©2017 State of Michigan
FILED June 1, 2017

S T A T E O F M I C H I G A N

SUPREME COURT

PEOPLE OF THE STATE OF MICHIGAN,

Plaintiff-Appellee,

v No. 153115

MICHAEL CHRISTOPHER FREDERICK,

Defendant-Appellant.

PEOPLE OF THE STATE OF MICHIGAN,

Plaintiff-Appellee,

v No. 153117

TODD RANDOLPH VAN DOORNE,

Defendant-Appellant.

BEFORE THE ENTIRE BENCH 

Michigan Supreme Court

Lansing, Michigan

OPINION Chief Justice:

Stephen J. Markman

Justices:

Brian K. Zahra

Bridget M. McCormack

David F. Viviano

Richard H. Bernstein

Joan L. Larsen

Kurtis T. Wilder
2

MCCORMACK, J.

In these consolidated cases, we consider the constitutionality of two early morning 

searches of the defendants’ homes. We conclude that the police conduct in both cases

was unconstitutional; these were not permissible “knock and talks,” but rather warrantless 

searches. Because of these illegal searches, the defendants’ consent to search—even if 

voluntary—is invalid unless it is sufficiently attenuated from the illegality. Accordingly, 

we reverse the Court of Appeals’ contrary determination and remand these cases to the 

Kent Circuit Court for further proceedings. 

I. FACTS AND PROCEDURAL HISTORY

During the predawn hours on March 18, 2014, seven officers from the Kent Area 

Narcotics Enforcement Team (KANET) made unscheduled visits to the defendants’ 

homes. Both defendants were employees of the corrections division of the Kent County 

Sheriff Department. Their names had come up in a criminal investigation, and KANET 

decided to perform these early morning visits to the defendants’ homes rather than 

waiting until daytime to speak with the defendants (or seeking search warrants). KANET 

knocked on defendant Michael Frederick’s door around 4:00 a.m. and on defendant Todd 

Van Doorne’s door around 5:30 a.m. Lieutenant Al Roetman, who was present at both 

searches, testified that everyone appeared to be asleep at both houses.

Both defendants and their families were surprised and alarmed by the intrusions. 

Van Doorne considered arming himself, as did Frederick’s wife. Nonetheless, both 

defendants answered the door after a few minutes of knocking—each thinking that there 

must have been some sort of emergency. 
3

Instead, each defendant found himself confronted with a group of police officers.

The officers asked each defendant about marijuana butter that they suspected the 

defendants possessed. After a conversation with each defendant, during which the 

defendants were read their Miranda1 rights, both defendants consented to a search of 

their homes and signed a consent form to that effect. Marijuana butter and other 

marijuana products were recovered from each house. 

The defendants were charged with various drug offenses. Both moved to suppress 

evidence of the marijuana products found in their homes. The trial court denied both 

motions. The court concluded that KANET had not conducted a search by approaching 

the home and knocking, and that the subsequent consent search was a valid, voluntary 

search. The court distinguished Florida v Jardines, 569 US ___; 133 S Ct 1409; 185 L 

Ed 2d 495 (2013), noting that the police here did not use a drug-sniffing dog or otherwise 

try to search the home without knocking. Rather, because the police approached the 

home and knocked, the trial court held that these were valid knock and talks. 

The defendants sought interlocutory leave to appeal, which the Court of Appeals 

denied. The defendants then sought leave to appeal in this Court. In lieu of granting 

leave to appeal, we remanded the cases to the Court of Appeals for consideration as on 

leave granted. People v Frederick, 497 Mich 993 (2015); People v Van Doorne, 497 

Mich 993 (2015). We directed the Court of Appeals to address “whether the ‘knock and 

talk’ procedure conducted in [these cases] is consistent with US Const, Am IV, as 

 1 Miranda v Arizona, 384 US 436; 86 S Ct 1602; 16 L Ed 2d 694 (1966).
4

articulated in Florida v Jardines . . . .” Frederick, 497 Mich 993; Van Doorne, 497 Mich 

993. 

On remand, the Court of Appeals issued a split opinion. The majority concluded 

that the knock and talk procedures at issue were permitted by the Fourth Amendment. 

People v Frederick, 313 Mich App 457, 461; 886 NW2d 1 (2015). The majority 

emphasized that the officers approached the home, knocked, and waited to be received,

and “Jardines plainly condones such conduct.” Id. at 469. Though the police visits here 

occurred during the early morning hours, the majority concluded that they were 

nonetheless within the scope of the implied license because homeowners would be 

unsurprised to find a predawn visitor delivering a newspaper or seeking emergency 

assistance. Id. at 481.

Judge SERVITTO dissented. She concluded that the police conduct violated the 

defendants’ Fourth Amendment rights. Id. at 496 (SERVITTO, J., dissenting). First, Judge 

SERVITTO noted that the Jardines majority and dissent had seemed to agree, in dicta, that 

nighttime visits would be outside the scope of the implied license. Id. at 487-488. 

Further, Judge SERVITTO reasoned that the validity of a knock and talk is premised on 

“the implied license a homeowner extends to the public-at-large.” Id. at 496. Because 

the hours the police arrived at the defendants’ homes are not times at which most 

homeowners expect visitors, she concluded that the visits were outside the scope of a

proper knock and talk. Id.
5

II. ANALYSIS

In general, a search or seizure within a home or its curtilage without a warrant is 

per se an unreasonable search under the Fourth Amendment. People v Champion, 452 

Mich 92, 98; 549 NW2d 849 (1996); Katz v United States, 389 US 347, 357; 88 S Ct 507; 

19 L Ed 2d 576 (1967). Two arguments have been presented as to why this police 

conduct was lawful. First, the prosecution argues that the initial approach was a knock 

and talk, not a search. Second, the prosecution argues that the search that followed that 

initial approach was a consent search. 

A. KNOCK AND TALK

A “knock and talk,” when performed within its proper scope, is not a search at all. 

Jardines, 569 US at ___; 133 S Ct at 1415. The proper scope of a knock and talk is 

determined by the “implied license” that is granted to “solicitors, hawkers, and peddlers 

of all kinds.” Id. at ___; 133 S Ct at 1415 (citation and quotation marks omitted). “Thus, 

a police officer not armed with a warrant may approach a home and knock, precisely 

because that is ‘no more than any private citizen might do.’ ” Id. at ___; 133 S Ct at 

1416, quoting Kentucky v King, 563 US 452, 469; 131 S Ct 1849; 179 L Ed 2d 865

(2011).

In Jardines, the police approached a house via the front walk with a drug dog. 

Jardines, 569 US at ___; 133 S Ct at 1413. The dog alerted, indicating that it smelled 

contraband, and eventually sat at the front door of the home, where the odor was 

strongest. Id. Using this information, the police obtained a warrant, and their search of 

the home revealed marijuana plants. Id. 
6

Justice Scalia, writing for the Court, employed a property-rights framework2 to 

conclude that the prewarrant conduct of the police constituted a search. The Court

distinguished the case from King, in which the Court had held that a knock and talk was 

not a search, because the police in Jardines, unlike the police in King, had trespassed; 

although the public, and thus the police, generally have an implied license to “approach 

the door by the front path, knock promptly, wait briefly to be received, and then (absent 

invitation to linger longer) leave,” the police in Jardines had not complied with the scope 

of that implied license. Id. at ___; 133 S Ct at 1415-1416. “[I]ntroducing a trained police 

dog to explore the area around the home in hopes of discovering incriminating evidence 

 2 In Katz v United States, 389 US 347, the Court broke with tradition by considering not 

whether the government had trod on the defendant’s property interests, but rather whether 

it had violated his privacy interests. Subsequently, the Court clarified that Katz had not 

replaced the property-interests test; Katz merely added to it. Alderman v United States, 

394 US 165, 180; 89 S Ct 961; 22 L Ed 2d 176 (1969) (“[W]e [do not] believe that Katz, 

by holding that the Fourth Amendment protects persons and their private conversations, 

was intended to withdraw any of the protection which the Amendment extends to the 

home . . . .”).

The Court reaffirmed the importance of the property-rights analysis in the Fourth 

Amendment context in United States v Jones, 565 US 400; 132 S Ct 945; 181 L Ed 2d 

911 (2012). In that case, the Court held that the warrantless installation of a GPS 

tracking device on the exterior of a Jeep and subsequent tracking of the defendant’s 

movements on public roads constituted a search, despite the Court’s earlier holdings that 

tracking of a defendant’s movements on public roads was not a search. Id. at 404; cf. 

United States v Knotts, 460 US 276; 103 S Ct 1081; 75 L Ed 2d 55 (1983) (holding that 

no search occurred when law enforcement tracked on public roads the location of a 

beeper that had been installed in a container before the defendant’s possession of the 

container). The Jones Court distinguished Knotts on the ground that it did not involve a 

trespass. Jones, 565 US at 409-410. The violation of Jones’s property rights, combined 

with the subsequent information-gathering, constituted a search. Id. at 407-408. The 

Court cautioned that “[t]respass alone does not qualify, but there must be conjoined with 

that . . . an attempt to find something or to obtain information.” Id. at 408 n 5.
7

is something else. There is no customary invitation to do that.” Id. at ___; 133 S Ct at 

1416. Thus, the police had trespassed on Fourth-Amendment-protected property.3 Id.

Consistently with United States v Jones, 565 US 400; 132 S Ct 945; 181 L Ed 2d 

911 (2012), the Jardines Court required not only a trespass, but also some attempted

information-gathering, to find that a search had occurred. Jardines, 569 US at ___; 133 S 

Ct at 1414; Jones, 565 US at 408 n 5 (“[P]ost-Katz we have explained that an actual 

trespass is neither necessary nor sufficient to establish a constitutional violation. . . . 

Trespass alone does not qualify [as a search], but there must be conjoined with that . . . an 

attempt to find something or to obtain information.”) (citations and quotation marks 

omitted). The Jardines Court concluded that the police conduct there included 

information-gathering, such that the behavior constituted a warrantless search of the 

curtilage. Jardines, 569 US at ___; 133 S Ct at 1417.

It is also clear from Jones and Jardines that “information-gathering” is not 

synonymous with a Fourth Amendment “search.” Both Jones and Jardines held that 

conduct that would not amount to a search, standing alone, was nonetheless informationgathering. The information-gathering in Jardines was the use of a drug-sniffing dog—

conduct that the Supreme Court of the United States has held is not a search when the 

 3 The Jardines Court distinguished between trespasses that implicate the Fourth 

Amendment and those that do not. For instance, police may trespass and search in open 

fields without violating the Fourth Amendment because “an open field . . . is not one of 

those protected areas enumerated in the Fourth Amendment.” Jones, 565 US at 411, 

citing Oliver v United States, 466 US 170, 177; 104 S Ct 1735; 80 L Ed 2d 214 (1984). 

But because the curtilage is part of the home, Oliver, 466 US at 180, and homes are 

protected by the Fourth Amendment, trespassing on the curtilage implicates Fourth 

Amendment protections. 
8

police have not trespassed. Id. at ___; 133 S Ct at 1414; Illinois v Caballes, 543 US 405, 

410; 125 S Ct 834; 160 L Ed 2d 842 (2005) (holding that a dog sniff conducted during a 

lawful traffic stop did not implicate legitimate privacy interests). Similarly, in Jones, the 

information-gathering was the tracking of the defendant’s location on public streets—

conduct that the Supreme Court has also held is not a search when the police have not 

trespassed. Jones, 565 US at 408 n 5; United States v Knotts, 460 US 276, 285; 103 S Ct 

1081; 75 L Ed 2d 55 (1983) (holding that a person traveling in an automobile on public 

roads has no reasonable expectation of privacy in his or her location). But informationgathering that is not a search nevertheless becomes a search when it is combined with a 

trespass on Fourth-Amendment-protected property.4

In Jardines, the majority and dissenting opinions address in dicta one issue that is 

particularly relevant here. In his dissent, Justice Alito noted that, “as a general 

matter, . . . a visitor [may not] come to the front door in the middle of the night without 

an express invitation.” Jardines, 569 US at ___; 133 S Ct at 1422 (Alito, J., dissenting). 

In response, the majority opinion reasoned that the dissent “quite rightly” relied on the 

fact that a nighttime knock would be alarming in concluding that nightime visits would 

be outside the scope of the implied license. Id. at ___; 133 S Ct at 1416 n 3 (opinion of 

the Court) (“We think a typical person would find it a cause for great alarm (the kind of 

 4 For example, looking into the windows of a home from a sidewalk or other public area 

is not a search. But it is information-gathering, such that, if the police trespass on the 

home’s curtilage and peer through the windows from that vantage point, they have 

conducted a search. The trespass converts conduct that would not otherwise constitute a 

search into a search.
9

reaction the dissent quite rightly relies upon to justify its no-night-visits rule) to find a 

stranger snooping about his front porch with or without a dog.”) (citation, quotation 

marks, and emphasis omitted). Thus, the Jardines Court apparently agreed, albeit in 

dicta, that a nighttime visit would be outside the scope of the implied license (and thus a 

trespass). 

We believe, as the Supreme Court suggested in Jardines, that the scope of the 

implied license to approach a house and knock is time-sensitive. Id. at ___; 133 S Ct at 

1416 n 3; id. at ___; 133 S Ct at 1422 (Alito, J., dissenting). Just as there is no implied 

license to bring a drug-sniffing dog to someone’s front porch, there is generally no 

implied license to knock at someone’s door in the middle of the night. See id. at ___; 133 

S Ct at 1416 (opinion of the Court) (“There is no customary invitation to do that.”). This 

custom was apparent to the investigating officers in this case. KANET officers testified

candidly that it would be inappropriate for Girl Scouts or other visitors to knock on the 

door in the middle of the night, but evidently the officers believed that they were not 

bound by these customs.5

 But a knock and talk is not considered a governmental 

intrusion precisely because its contours are defined by what anyone may do. King, 563 

US at 469 (“When law enforcement officers who are not armed with a warrant knock on 

a door, they do no more than any private citizen might do.”). When the officers stray 

 5 In fact, multiple KANET members testified that they performed knock and talks in the 

middle of the night on a regular basis. Roetman testified that “[j]ust because it hits the 

stroke of midnight doesn’t mean our case stops and we don’t keep going to people’s 

homes, whether it’s a marijuana case or an armed robbery. . . . I don’t know what you’re 

getting at.” 
10

beyond what any private citizen might do, they have strayed beyond the bounds of a 

permissible knock and talk; in other words, the officers are trespassing. That is what 

happened here. The reasoning that leads us to conclude that these visits were outside the 

scope of the implied license is not nuanced or complicated. As the Jardines Court aptly 

explained, Girl Scouts and trick-or-treaters regularly manage to abide by the terms of the 

implied license. See Jardines, 569 US at ___; 133 S Ct at 1415 (“Complying with the 

terms of that traditional invitation does not require fine-grained legal knowledge; it is 

generally managed without incident by the Nation’s Girl Scouts and trick-or-treaters.”). 

And, as any Girl Scout knows, the “background social norms that invite a visitor to the 

front door,” id. at ___; 133 S Ct at 1416, typically do not extend to a visit in the middle of 

the night. See United States v Lundin, 817 F3d 1151, 1159 (CA 9, 2016) (“[U]nexpected 

visitors are customarily expected to knock on the front door of a home only during 

normal waking hours.”). Thus, we hold that the police were trespassing when they 

approached the defendants’ homes.6

The Court of Appeals majority reasoned that the implied license extended to 

midnight visitors seeking emergency assistance or delivering the newspaper and therefore 

it extended, too, to the police conduct here. We find these examples unhelpful. 

Newspaper delivery services have express permission to be on the property; therefore, 

 6 We need not decide precisely what time the implied license to approach begins and 

ends. In these cases, there were no circumstances that would lead a reasonable member 

of the public to believe that the occupants of the respective homes welcomed visitors at 

4:00 a.m. or 5:30 a.m. Accordingly, we believe it is clear that these approaches were 

outside the scope of the implied license.
11

their conduct is irrelevant when considering the implied license to approach a house.7

And the fact that a visitor may approach a home in an emergency does not mean that a 

visitor who is not in an emergency may approach. Emergencies justify conduct that 

would otherwise be unacceptable; they are exceptions to the rule, not the rule.8 Because 

we conclude that the implied scope of the license does not extend to these predawn 

approaches, we hold that the police were trespassing.

Having concluded that the police conduct was a trespass on Fourth-Amendmentprotected property, we next turn to whether the police were seeking “to find something or 

to obtain information,” such that the Fourth Amendment is implicated. Jones, 565 US at 

408 n 5. A police officer walking through a neighborhood who takes a shortcut across 

the corner of a homeowner’s lawn has trespassed. Yet that officer has not violated the 

Fourth Amendment because, without some information-gathering, no search has 

occurred. In these cases, however, the police were seeking information; therefore, their 

conduct implicated the Fourth Amendment. The KANET officers were not simply 

cutting across the defendants’ lawns as a shortcut, stopping by to drop off a get-well-soon 

basket, or visiting the homes to regretfully inform the defendants that a loved one had 

 7 Moreover, most newspaper delivery services have permission to leave newspapers on 

the property, not to approach the house and knock. Most homeowners would be 

surprised—and likely indignant—if their newspaper delivery person rang the bell and 

knocked for several minutes at 5:00 a.m. rather than simply leaving the paper. 

8 See Ploof v Putnam, 81 Vt 471; 71 A 188, 189 (1908) (“It is clear that an entry upon the 

land of another may be justified by necessity . . . .”); Vincent v Lake Erie Transp Co, 109 

Minn 456, 460; 124 NW 221 (1910) (holding that trespass onto the property of another 

may be justified by necessity).
12

been injured in an accident. The officers approached each house to obtain information 

about the marijuana butter they suspected each defendant possessed. This intent is 

sufficient to satisfy the information-gathering prong of the Jones test.

That the officers intended to get permission to search for the marijuana butter does 

not alter our analysis. We agree with the prosecution that, as King established and 

Jardines affirmed, “it is not a Fourth Amendment search to approach the home in order to 

speak with the occupant, because all are invited to do that. The mere purpose of 

gathering information in the course of engaging in that permitted conduct does not cause 

it to violate the Fourth Amendment.” Jardines, 569 US at ___; 133 S Ct at 1416 n 4

(citations, quotation marks, and emphasis omitted), citing King, 563 US at 469-470. True 

enough; approaching a home with the purpose of gathering information is not, standing 

alone, a Fourth Amendment search. King, 563 US at 469-470. But, as noted above, 

when “conjoined” with a trespass, information-gathering—which need not qualify as a 

search, standing alone—is all that is required to turn the trespass into a Fourth 

Amendment search. Jones, 565 US at 408 n 5. The officers here plainly approached the 

defendants’ homes for the purpose of gathering information.9

The fact that the officers sought to gather their information by speaking with the 

homeowners rather than by peering through windows or rummaging through the bushes 

is irrelevant. What matters is that they sought to gather information by way of a trespass

on Fourth-Amendment-protected property. That they did. The approaches of the 

 9 Detective Todd Butler, one of the KANET members who participated in the knock and 

talk, testified that “[t]he only reason we were there is because of the drugs.” 
13

defendants’ homes were not valid knock and talks, but rather searches under the Fourth 

Amendment. And because the police did not have warrants or any other exception to the 

warrant requirement, we conclude that the approaches violated the Fourth Amendment.

B. CONSENT

This is not the end of the analysis, however. During the invalid knock and talks, 

each defendant consented to a search of his respective home. Consent searches, when 

voluntary, are an exception to the warrant requirement. Schneckloth v Bustamonte, 412 

US 218, 219; 93 S Ct 2041; 36 L Ed 2d 854 (1973). The voluntariness question turns on

whether a reasonable person would, under the totality of the circumstances, feel able to 

choose whether to consent. Id. at 227.

The defendants believe that their consent, even if voluntary, is irrelevant, given the 

contemporaneous Fourth Amendment violation. The prosecution views the Fourth 

Amendment violation as irrelevant, given the subsequent consent. Neither is correct. 

The defendants’ consent is not irrelevant—but neither is it evaluated separately from the 

illegal searches. 

Rather, the defendants’ consent—even if voluntary—is invalid unless it is

sufficiently attenuated from the warrantless search. The Supreme Court has repeatedly 

held that evidence obtained through an illegal search or seizure is tainted by that initial

illegality unless sufficiently attenuated from it. See Wong Sun v United States, 371 US 

471, 486; 83 S Ct 407; 9 L Ed 2d 441 (1963) (holding that evidence acquired after an 

illegal search must be suppressed unless the government shows that its acquisition of the 

evidence resulted from “an intervening independent act of free will” sufficient “to purge 
14

the primary taint of the unlawful invasion”). That analysis has been applied to both 

consensual statements and—particularly relevant here—consensual searches. Brown v 

Illinois, 422 US 590, 602; 95 S Ct 2254; 45 L Ed 2d 416 (1975) (holding that when an 

inculpatory statement follows an unlawful arrest, a finding of voluntariness does not 

obviate the need to make a separate Fourth Amendment determination as to whether the 

statement was “ ‘sufficiently an act of free will to purge the primary taint’ ”), quoting 

Wong Sun, 371 US at 486; Florida v Royer, 460 US 491, 507-508; 103 S Ct 1319; 75 L 

Ed 2d 229 (1983) (“Because we affirm the . . . conclusion that Royer was being illegally 

detained when he consented to the search of his luggage, we agree that the consent was 

tainted by the illegality and was ineffective to justify the search.”).

Thus, even when consent is voluntary, if it is not attenuated from the

unconstitutional search, the evidence must be suppressed. Wong Sun, 371 US at 486; 

Brown, 422 US at 602; Royer, 460 US at 507-508. The Supreme Court has identified 

three factors to be considered in determining whether consent is sufficiently attenuated: 

(1) the temporal proximity of the illegal act and the alleged consent, (2) the presence of 

intervening circumstances, and (3) the purpose and flagrancy of the official misconduct. 

Brown, 422 US at 603-604. 

In these cases, because the trial court determined that there was no Fourth 

Amendment violation, it did not consider whether the subsequent consent was attenuated 

from the illegality. Therefore, we remand to that court for consideration of that question 

in the first instance.
15

III. CONCLUSION

A proper application of Fourth Amendment jurisprudence requires us to reverse 

the Court of Appeals. Because these knock and talks were outside the scope of the 

implied license, the officers trespassed on Fourth-Amendment-protected property. And 

because the officers trespassed while seeking information, they performed illegal 

searches. Finally, because of these illegal searches, the defendants’ consent—even if 

voluntary—is nonetheless invalid unless it was sufficiently attenuated from the illegality.

We therefore reverse the Court of Appeals and remand these cases to the Kent Circuit 

Court to determine whether the defendants’ consent to search was attenuated from the 

officers’ illegal search. 

Bridget M. McCormack

Stephen J. Markman

Brian K. Zahra

David F. Viviano

Richard H. Bernstein

Joan L. Larsen

Kurtis T. Wilder