In the
 United States Court of Appeals
              For the Seventh Circuit
                        ____________

No. 02-1737
UNITED STATES OF AMERICA,
                                           Plaintiff-Appellee,
                              v.

REAL PROPERTY LOCATED AT
15324 COUNTY HIGHWAY E.,
RICHLAND CENTER, RICHLAND
COUNTY, WISCONSIN,
                                                    Defendant,
                             and

CHARLES J. ACKER,
                                         Claimant-Appellant.
                        ____________
          Appeal from the United States District Court
              for the Western District of Wisconsin.
         No. 98 C 718—Barbara B. Crabb, Chief Judge.
                        ____________
    ARGUED DECEMBER 5, 2002—DECIDED JUNE 18, 2003
                   ____________


 Before BAUER, DIANE P. WOOD, and WILLIAMS, Circuit
Judges.
  BAUER, Circuit Judge. Appellant Charles J. Acker chal-
lenges the district court’s denial of his motion to sup-
press evidence and resulting order of forfeiture to the
United States of his house consequent to the discovery
therein of a marijuana cultivation and distribution opera-
2                                                 No. 02-1737

tion. Acker claims that evidence of his violations of fed-
eral controlled substance laws should have been excluded
from the forfeiture proceeding because law enforcement
agents searched his residence in violation of his Fourth
Amendment rights. Because we conclude that law enforce-
ment agents acted in objectively reasonable reliance upon
a warrant issued in accordance with the law as it then
existed, and that, therefore, the evidence is not subject
to suppression, we affirm the decision of the district court.


                      BACKGROUND
  In March 1998, during the course of their investigation
of Acker’s suspected marijuana cultivation and distribu-
tion activities, Wisconsin Division of Narcotics Enforce-
ment (“DNE”) Special Agent Pete Thelen and Richland
County Deputy Sheriff Rick Wickland scanned Acker’s
house for thermal images without first obtaining a search
warrant. Thelen, a certified thermographer, concluded that
the uneven heat fields radiating from the house were
consistent with the heat typically generated from an in-
door marijuana growing operation.1
   In addition to the thermal imaging data, Wickland
included the following information in an affidavit in sup-
port of probable cause to search Acker’s house: (i) that
a confidential informant told Wickland in July or August
1997 that “Chuck Acker sells a lot of marijuana” and
lives in Sylvan Township in Richland County, and that
Wickland independently verified that Charles J. Acker lived
at 15432 County Highway E., Richland Center, Sylvan
Township, Richland County; (ii) that, in December 1997, a



1
  Elevated heat levels are a product of the powerful lights used
to enable photosynthesis and to control the timing of growth
cycles during indoor plant cultivation.
No. 02-1737                                                3

second confidential informant, whose reliability Wickland
had ascertained from the informant’s cooperation with
authorities on three previous occasions, stated that a
neighbor purchased marijuana from an individual known as
“Chuck” living near both Highway 14 and the Richland/
Vernon county line, and that Wickland independently
verified that Acker’s residence was located within two
miles of the county line; (iii) that Acker’s electrical rec-
ords for the period April 1996 to January 1998 indicated
usage hours that, based on Wickland’s cannabis enforce-
ment training, he knew to be consistent with usage patterns
associated with indoor growing operations; (iv) that
DNE Special Agent Loreen Tryba informed Wickland that
Acker’s father cultivated orchids using a controlled hydro-
ponic system; and (v) that surveillance of Acker’s residence
revealed that the basement windows were “blocked out,”
which, in Thelen’s opinion, was consistent with efforts
typical of indoor marijuana growers to prevent heat emana-
tion. On the basis of Wickland’s affidavit, a Wisconsin
Circuit Court judge in Richland County signed a search
warrant authorizing the Richland County Sheriff’s De-
partment to search Acker’s residence.
  During their execution of the search warrant, law enforce-
ment officers seized 40 cannabis plants, 2955 grams of
harvested marijuana, 86.5 grams of processed marijuana
packaged in sealable plastic bags, seven bags of starter
soil, four 1000-watt lights with ballasts, five light timers,
two exhaust fans, a triple-beam scale, notes and a notebook
describing the growing operation, and drug paraphernalia.
DNE agents advised Acker of his constitutional rights,
which he waived in writing prior to stating that he had
cultivated cannabis in his house continuously during
the previous 18 months, selling 30 to 40 ounces per four-
month harvest cycle for approximately $175 per ounce.
  In October 1998, the government filed a civil action for
the forfeiture of Acker’s house pursuant to 21 U.S.C. § 881,
4                                                    No. 02-1737

which provides, in relevant part, for the forfeiture to
the United States of property used in the commission of
federal controlled substance violations punishable by
more than one year of imprisonment.2 Acker moved to
suppress evidence of his violation and to dismiss the
complaint, asserting that the thermal imaging scan,
conducted without a search warrant, amounted to an
unreasonable search in violation of his Fourth Amend-
ment rights. In denying Acker’s motions, the district
court followed this Court’s holding in United States v.
Myers that “thermal imaging scanning does not constitute
a search within the meaning of the Fourth Amendment.”

, 669 (7th Cir. 1995). This Court affirmed
the district court’s resulting judgment of forfeiture. United
States v. 15324 County Highway E., 

(7th Cir.
2000).
  In 2001, the United States Supreme Court granted
Acker’s petition for certiorari and, on the basis of its
decision in Kyllo v. United States, 

, 36 (2001)


2
  Relevant provisions of Title XXI of the United States Code
include the following:
    All real property, including any right, title, and interest
    (including any leasehold interest) in the whole of any lot or
    tract of land and any appurtenances or improvements, which
    is used, or intended to be used, in any manner or part, to
    commit, or to facilitate the commission of, a violation of
    this subchapter punishable by more than one year’s impris-
    onment . . . shall be subject to forfeiture to the United States
    and no property right shall exist in [it].
21 U.S.C. § 881(a)(7) (2003). Based solely on the quantity of
marijuana seized from Acker’s home (excluding the distribution
of additional quantities admitted in his statements to DNE
agents), his manufacture and possession of a controlled sub-
stance with intent to distribute is punishable by as many as
five years’ imprisonment. See 

No. 02-1737                                                5

(holding that warrantless “thermal-imaging observations
of the intimate details of a home are impermissible”),
vacated this Court’s affirmance and remanded the case
for our further consideration. Acker v. United States, 

(2001). Noting in an unpublished opinion that,
after Kyllo, “our decisions in Myers and in the present
case can no longer stand,” this Court vacated the district
court’s judgment and remanded the case for further dis-
trict court proceedings consistent with the holding of Kyllo.
  On remand, the district court considered the sufficiency
of the affidavit absent the thermal imaging evidence and
concluded that it did not establish probable cause. It did
determine, however, that the officers conducting the
thermal imaging scan acted in good-faith reliance upon
the law then in force under Myers and, analogizing to
Illinois v. Krull, 

(1987) (holding that evi-
dence seized by officers acting in good-faith reliance upon
statute authorizing warrantless administrative searches—
later invalidated on constitutional grounds—is not sub-
ject to the exclusionary rule), applied the good-faith excep-
tion to the exclusionary rule as originally articulated in
United States v. Leon, 

(1984). As a result, the
district court again denied Acker’s motions to suppress
and to dismiss and granted the district court’s motion for
summary judgment, thereby ordering the forfeiture of
Acker’s house.
  This appeal ensued.


                        ANALYSIS
  Ordinarily, evidence obtained in contravention of the
Fourth Amendment’s prohibition on unreasonable searches
and seizures is subject to exclusion from the prosecution’s
case-in-chief. Mapp v. Ohio, 

(1961). In Leon,
the United States Supreme Court established an excep-
tion to this exclusionary rule in cases where, notwith-
6                                                No. 02-1737

standing a conceded Fourth Amendment violation, law
enforcement officers have acted in good-faith reliance
upon a search warrant validly issued by a detached and
neutral 

(BLACKMUN, J., concur-
ring in judgment). The Court reasoned that the suppres-
sion of evidence obtained through magistrate error inade-
quately served the exclusionary rule’s underlying pur-
pose: to deter law enforcement agents from overstepping
the bounds of the Fourth Amendment. 

(observ-
ing that “penalizing the officer for the magistrate’s error,
rather than his own, cannot logically contribute to the
deterrence of Fourth Amendment violations”).
  Premised, as it is, on a law enforcement agent’s good-
faith reliance on a search warrant, the Leon exception is
inapplicable, and suppression is therefore appropriate, in
any of the following circumstances: (i) in issuing the
search warrant, the magistrate relied on an affidavit
that the affiant knew was false or would have known
was false but for his or her recklessness; (ii) the magis-
trate wholly abandoned his or her detached and neutral
judicial role; (iii) the affidavit’s dearth of reliable indicia
of probable cause renders official belief in its existence
entirely unreasonable; or (iv) the affidavit is so facially
deficient that executing agents could not reasonably
presume it to be valid. 

(internal citations omit-
ted).
  The Supreme Court subsequently extended the applica-
bility of the Leon good-faith exception to situations where
a law enforcement agent conducts a warrantless admin-
istrative search in objectively reasonable reliance upon
an authorizing statute that is later declared unconstitu-
tional, reasoning that suppression of evidence seized in
such manner “would have as little deterrent effect on the
officer’s actions as would the exclusion of evidence when
an officer acts in objectively reasonable reliance on a
warrant.” 

.
No. 02-1737                                                7

   In support of his motion to suppress, Acker argued
that the evidence seized pursuant to the search warrant
was the tainted fruit of the initial warrantless thermal
imaging scan. He urged the district court to exclude the
evidence based on an application of the “independent
source” doctrine, articulated in United States v. Murray,

(1988). In that case, federal agents observed
bales of marijuana inside a warehouse after their war-
rantless forced entry thereto; then, neither disclosing the
illegal search to the issuing magistrate nor relying on
evidence observed therein, they obtained and executed a
warrant to search the warehouse. The Supreme Court
explained that the controlling issue in determining the
admissibility of evidence seized pursuant to the warrant
(assuming, of course, that alternative, legally obtained
evidence presented to the magistrate established the
existence of probable cause) was not whether the agents
could have obtained a search warrant absent the illegally
observed evidence, but rather, whether they would have
sought one absent their knowledge of its existence. 

. If, on remand, the district court found that
agents otherwise would not have sought the search war-
rant, then it should exclude the evidence as lacking a
source independent from the illegal search. Applying
the Murray independent source doctrine in a later case,
this Court clarified that the analysis raises two questions,
the first being “whether the illegally obtained evidence
affected the magistrate’s decision to issue the search
warrant,” and the second, whether the agent’s decision to
seek the warrant was motivated by his knowledge of that
evidence. United States v. Markling, 

, 1315-16
(1993).
  The district court implicitly entertained Acker’s invoca-
tion of the independent source doctrine in its statement
that “resolving [Markling’s] first question obviates answer-
ing the second, because the warrant application lacks a
8                                                No. 02-1737

showing of probable cause.” Rather than suppress the
evidence, however, the district court cited Krull as au-
thority for application of the good-faith exception to the
exclusionary rule, finding that Wickland and Thelen
scanned Acker’s residence in objectively reasonable reli-
ance upon this Court’s decision in Myers. Though it ac-
knowledged the distinction between these agents’ reliance
on case law and the Krull agents’ reliance on statute, the
district court dismissed it as immaterial: “In either event,
the analysis and result would be the same: would sup-
pressing the evidence obtained in the search advance
the deterrence purposes of the exclusionary rule? If not,
the search results would not be suppressed.” The district
court concluded that Wickland and Thelen acted in confor-
mity with the law and therefore applied the good-faith
exception in order to deny Acker’s motion to suppress.
  In our review, for plain error, of the district court’s
application of the good-faith exception, United States v.
Spry, 

, 834 (7th Cir. 1999) (citation omitted),
we need not decide—and afford the district court a pre-
sumption of correctness with respect to—the issue of the
(non)existence of probable cause, see United States v.
Fairchild, 

, 264 (7th Cir. 1991) (assuming
without deciding that officer’s affidavit failed to establish
probable cause, but holding that good-faith exception
applied).
  Although the good-faith exception is the proper basis,
generally speaking, for refusing to suppress evidence seized
from Acker’s residence, we reject the district court’s assign-
ment of undue analytical weight to the agents’ reliance
upon Myers to conduct the thermal imaging scan and,
accordingly, its inapposite analogy to Krull. Rather, under
a more conventional Leon analysis, resort to the excep-
tion is compelled by the agents’ reasonable reliance upon a
validly issued search warrant to seize the challenged
evidence.
No. 02-1737                                                     9

  To defeat the application of the good-faith exception to
the evidence seized in violation of his Fourth Amendment
rights under Kyllo but pursuant to a validly issued search
warrant, Acker must demonstrate some misconduct on
the part of law enforcement agents.3 He has made no such
showing. Significantly, the affidavit in support of probable
cause that Wickland presented to the state court judge
explicitly mentioned the thermal imaging scan; that is,
the source and substance of the evidence in question.
Although the Supreme Court would eventually declare
such warrantless use of thermal imaging unconstitutional,
it did not do so until June 2001, more than three years
later. Moreover, the state court judge implicitly sanc-
tioned the agents’ actions in his finding of probable cause
and resulting issuance of the search warrant. Thus, to the
extent that any actor can be said to have been at fault,
it was not the officers who sought, obtained, and exe-
cuted the warrant, but rather the magistrate who, lacking
the requisite prescience (not to mention authority, given
Myers) to declare the unconstitutionality of the scan, relied
on the then-controlling precedent to deny its issuance.
On the other hand, the belief of an officer—warrant-in-
hand—that probable cause existed to search Acker’s
residence was entirely reasonable. In this respect, the case


3
   Since the Fourth Amendment does not expressly preclude the
use of evidence obtained through its violation, and thus inclusion
of such evidence works no new Fourth Amendment wrong, the
exclusionary rule “operates as a judicially created remedy
designed to safeguard Fourth Amendment rights generally
through its deterrent effect, rather than a personal constitu-
tional right of the party aggrieved.” 

(quot-
ing United States v. Calandra, 

, 348, 354 (1974).
Moreover, application of the rule has been “limited to cases in
which the prosecution seeks to use the fruits of an illegal search
or seizure against the victim of police misconduct.” 

(internal citations omitted) (emphasis added).
10                                                   No. 02-1737

is distinguishable from a traditional “tainted warrant”
case, such as Murray, where agents conceal known or
reasonably knowable Fourth Amendment violations from
the issuing magistrate. Here, by contrast, after disclos-
ing fully their antecedent actions, law enforcement agents
properly left the probable cause determination, and its
attendant constitutional and precedential considerations,
to the better judgment of the magistrate. This distinction
is important for two closely related reasons. First, any
error that is said to have occurred must be attributed to
the magistrate, and not law enforcement agents, for the
former was in a relatively better position to divine the as-
yet unannounced unconstitutionality of the thermal im-
aging scan. Second, the candor of police with respect to
the scan precludes a court’s refusal to apply the good-
faith exception on the basis of police dishonesty or reck-
lessness before the issuing magistrate, the first of the
four enumerated situations in which the exception will
not apply.4 Both points highlight the reality that exclu-
sion of the challenged evidence would not adequately
advance the purpose of deterring police misconduct, but
rather would penalize police for magistral mistake.5
  That the preceding analysis obviates the district court’s
direct analogy to Krull is neither inadvertent nor inconse-


4
  Nor does Acker contend, nor do the facts indicate, that the
magistrate wholly abandoned his detached and neutral judicial
role, that the affidavit utterly lacked reliable indicia of probable
cause such that officers’ belief in its existence was entirely
unreasonable, or that the affidavit was so facially deficient
that executing agents could not reasonably have presumed its
validity.
5
   Although Krull does not control our disposition of this case, its
rationale is nonetheless instructive: “In determining whether
to apply the exclusionary rule, a court should examine whether
such application will advance the deterrent objective of the 

.
No. 02-1737                                               11

quential. We decline to extend further the applicability
of the good-faith exception to evidence seized during law
enforcement searches conducted in naked reliance upon
subsequently overruled case law—as distinguished from
the subsequently invalidated statute at issue in Krull—
absent magistrate approval by way of a search warrant.
Such expansion of the good-faith exception would have
undesirable, unintended consequences, principal among
them being an implicit invitation to officers in the field
to engage in the tasks—better left to the judiciary and
members of the bar more generally—of legal research
and analysis. Accordingly, we hold that evidence seized
by law enforcement agents acting in objectively reason-
able reliance upon a validly issued search warrant that,
through no misconduct on the part of the agents, rests on
a constitutionally flawed probable cause finding owing to
a subsequent change in controlling judicial precedent, is
not subject to the exclusionary rule.


                     CONCLUSION
  Because we find no reversible error in the district court’s
application of the good-faith exception to the exclusion-
ary rule, we AFFIRM the order denying Acker’s motion to
suppress evidence of violations of controlled substance
laws and granting summary judgment in favor of the
United States.

A true Copy:
       Teste:

                        ________________________________
                        Clerk of the United States Court of
                          Appeals for the Seventh Circuit

                   USCA-02-C-0072—6-18-03