State v. Ryan Alan Stenner

COURT OF APPEALS
DECISION NOTICE
DATED AND FILED This opinion is subject to further editing. If
published, the official version will appear in
the bound volume of the Official Reports.
May 7, 2026
A party may file with the Supreme Court a
Samuel A. Christensen petition to review an adverse decision by the
Clerk of Court of Appeals Court of Appeals. See WIS. STAT. § 808.10
and RULE 809.62.

Appeal No. 2025AP503-CR Cir. Ct. No. 2024CM112

STATE OF WISCONSIN IN COURT OF APPEALS
DISTRICT IV

STATE OF WISCONSIN,

PLAINTIFF-APPELLANT,

V.

RYAN ALAN STENNER,

DEFENDANT-RESPONDENT.

APPEAL from an order of the circuit court for Sauk County:
BLAKE J. DUREN, Judge. Reversed and cause remanded for further
proceedings.

¶1 TAYLOR, J.1 The State of Wisconsin appeals a circuit court order
granting defendant Ryan Alan Stenner’s motion to suppress evidence related to
1
This appeal is decided by one judge pursuant to WIS. STAT. § 752.31(2)(f) (2023-24).
All references to the Wisconsin Statutes are to the 2023-24 version.
No. 2025AP503-CR

charges for possession of cocaine in violation of WIS. STAT. § 961.41(3g)(c) and
possession of drug paraphernalia in violation of WIS. STAT. § 961.573(1). For the
reasons set forth below, I reverse and remand for further proceedings.

BACKGROUND

¶2 In February 2024, Baraboo Police Officer John Maginot conducted a
traffic stop of the car Stenner was driving for a possible illegal tint of the rear
window in violation of WIS. ADMIN. CODE § Trans 305.32(5)(b)(2), which I refer
to as the “rear window tinting rule.”2 When Maginot asked Stenner to open his
driver’s side door so Maginot could check the window decal identifying the type
of glass installed in the car, drug paraphernalia was observed in the driver’s-side
door handle. On further investigation, cocaine was also located in the car.
Stenner was arrested and charged with the illegal possession of cocaine and drug
paraphernalia.

¶3 Stenner moved to suppress all evidence obtained from the traffic
stop, arguing that Maginot lacked reasonable suspicion to conduct the stop. At the
evidentiary hearing on the motion, the State presented Maginot as their sole
witness.

¶4 Maginot testified that at the time of the stop, he was a police officer
with the Baraboo Police Department and had been in law enforcement since
2015.3 As a police officer with the Baraboo Police Department, Maginot typically
2
All references to WIS. ADMIN. CODE § Trans are to the March 2026 register, which
contains the same pertinent code provisions in effect at the time of the stop here.
3
At the time of his testimony at the suppression hearing, Maginot was no longer
working for the Baraboo Police Department but as a police officer for the Village of Shorewood
Hills Police Department.

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worked the night shift, from 5:00 p.m. until 5:00 a.m., and he made the majority of
his traffic stops during non-daylight hours. He estimated that he had been
involved in “anywhere from a hundred to a couple hundred” traffic stops involving
window tint issues.

¶5 Besides his police academy training at Blackhawk Technical College
and field training in various law enforcement roles, Maginot participated in an
eight-hour training in vehicle window tinting in December 2023 or January 2024.
At this training, Maginot was instructed, in pertinent part, on relevant standards
regarding the types of glass that are installed in different styles of vehicles and the
corresponding tinting requirements; how to visually estimate the degree of
window tint and identify an illegal tint; and how to use a tint meter, a device that
measures the light transmission through glass and identifies the precise percentage
of light traveling through the glass to the other side.

¶6 As to the window tint training, Maginot testified on the instruction
he received as follows. Different types of glass are installed by the manufacturer
on different styles of vehicles. The front windshields in all vehicles are typically
installed with an “AS1” glass. On passenger vehicles, including the car that
Stenner was driving on the morning at issue, the manufacturer typically installs an
“AS2” type of glass, on which a tint is applied during the original manufacturing
process that commonly allows for 70% of light transmission through the glass.
This percentage of tint is not visible to the naked eye and allows an external
observer to see through the windows into the vehicle. For multi-use vehicles, such
as SUVs and pick-up trucks, the manufacturer typically installs an “AS3” type of
glass that can be tinted with a lower light transparency on the back passenger and
rear windows. Maginot had never encountered a passenger vehicle with AS3

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glass. The specific glass type used in a vehicle is typically identified by a mylar
decal on the window of the vehicle.

¶7 Tinting outside of the original vehicle manufacturing process may
also occur, referred to as “aftermarket” tinting. Aftermarket tinting is typically
applied through the application of a film on the inside of the window, over the
manufacturer tint. If Maginot is following a passenger vehicle, and cannot see
through the back windows into the vehicle and identify the interior headrests or
occupants in the vehicle, he typically suspects that an illegal aftermarket tint may
have been applied to the windows. Another clue Maginot uses to aid in visually
identifying an illegal aftermarket tint on a passenger vehicle is to compare the
window tint on the vehicle in question with a front windshield band. Front
windshields may be equipped with a windshield band that appears near the top of
the windshield and can be darkly tinted to “the teens to single digit [percentage]
range” of light transmission to block sunlight from a driver’s eyes. Maginot can
visually identify when a passenger vehicle window is tinted as dark as a
windshield band, which enables Maginot to infer that the tint is possibly an illegal
aftermarket tint. Although Maginot can recognize by sight the difference between
a window tint with a 70% light transmittal compared to a window tint with a 15%
light transmittal, he cannot accurately determine the precise percentage of light
that transmits through a car window. This determination can only be made with
the use of a tint meter.

¶8 Concerning the stop of Stenner’s car, Maginot testified as follows.
In February 2024, at approximately 2:00 a.m., Baraboo Police Officer Nick Smith
notified Maginot that Smith was following a car for suspected illegal window
tinting and that the car had pulled into a gas station. Maginot located the car at the
gas station and parked his marked patrol car down the street, observing that the

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No. 2025AP503-CR

identified car which was parked at a gas pump was a passenger vehicle. When
Stenner drove the car out of the gas station parking lot, Maginot followed and
“observed that the rear back wind[ow] appeared to be entirely covered in
aftermarket tint,” and that the window appeared to him to be as dark as a front
windshield band, or, in other words, in the teens to single digit percentage range of
light transmission. Maginot suspected that the rear window had an illegal
aftermarket tint and initiated a traffic stop based on this suspected violation.

¶9 As Maginot approached the car on foot, he noted that the driver’s
side windows also appeared to be covered in aftermarket tint, similar to the rear
window. Maginot tested the driver’s side windows with his tint meter, taking two
test samples from the front driver’s side window and two samples from the rear
driver’s side window. The tint meter reported 14.6% light transmission for the
two samples taken from the driver’s side window and 13.8% and 13.9% light
transmission for the two samples taken from the rear driver’s side window.
Maginot did not test the rear window with his tint meter.

¶10 Maginot also attempted to check the mylar decal inside the car
indicating the type of glass installed by the manufacturer to confirm that it was
AS2 glass for passenger vehicles. It was at this point that drug paraphernalia was
observed in the driver’s-side door handle and cocaine was later discovered.
Stenner was arrested and charged as indicated.

¶11 Stenner moved to suppress all evidence that resulted from the traffic
stop, alleging that Maginot lacked reasonable suspicion to initiate the stop. The
circuit court conducted a hearing on the motion. After taking evidence and
hearing arguments, the court concluded that Maginot lacked reasonable suspicion
to stop Stenner’s car for an illegal rear window tint because: (1) Maginot was

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No. 2025AP503-CR

unable to determine whether Stenner’s rear window tint was applied by the
manufacturer or added as aftermarket tint; (2) Maginot was unable to determine
the precise percentage of light passing through the rear window; (3) the testimony
of Maginot that he stopped Stenner’s car because of the dark tinting in the rear
window was “very similar” to the testimony of the law enforcement officer in
State v. Conaway, 2010 WI App 7, 323 Wis. 2d 250, 779 N.W.2d 182, which this
court determined was inadequate to constitute reasonable suspicion; and
(4) “where there is at best a 50 percent chance that the law is in fact being
violated, the officer does not have the reasonable suspicion to justify a traffic
stop.” The court granted Stenner’s motion to suppress. The State appeals.

DISCUSSION

¶12 The State argues that the circuit court erred when it determined that
Maginot did not have reasonable suspicion to stop Stenner’s car for a possible
violation of the rear window tinting rule. Stenner argues that the court was correct
in determining that Maginot lacked reasonable suspicion that a traffic violation
was occurring or, in the alternative, that the rear window tinting rule is invalid and
unenforceable.4

4
Stenner’s brief does not comply with WIS. STAT. RULE 809.19(8)(bm), which
addresses the pagination of appellate briefs. See RULE 809.19(8)(bm) (providing that, when
paginating briefs, parties should use “Arabic numerals with sequential numbering starting at ‘1’
on the cover”). This rule was amended to its current form in 2021, see S. CT. ORDER 20-07, 2021
WI 37, 397 Wis. 2d xiii (eff. July 1, 2021), and the reason for the amendment is that briefs are
now electronically filed in PDF format, and are electronically stamped with page numbers when
they are accepted for eFiling. The pagination requirements ensure that the numbers on each page
of a brief “will match … the page header applied by the eFiling system, avoiding the confusion of
having two different page numbers” on every page of a brief. Supreme Court Note, 2021,
RULE 809.19.

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No. 2025AP503-CR

¶13 I conclude that the circuit court applied an incorrect legal standard to
its reasonable suspicion determination. Based on Maginot’s uncontroverted
testimony and the application of the correct legal standard, Maginot had
reasonable suspicion to stop Stenner’s car based on a possible violation of WIS.
ADMIN. CODE § Trans 305.32(5)(b)2. I also reject Stenner’s alternative argument
that the rear window tinting rule is invalid and unenforceable. Therefore, I
reverse.

I. Reasonable Suspicion

A. Applicable Legal Principles and the Standard of Review

¶14 The Fourth Amendment to the U.S. Constitution and Article I,
Section 11 of the Wisconsin Constitution protect individuals against unreasonable
government searches and seizures.5 State v. Tullberg, 2014 WI 134, ¶29 & n.17,
359 Wis. 2d 421, 857 N.W.2d 120. Wisconsin courts have historically interpreted
the search and seizure provision of our state’s constitution consistent with the
United States Supreme Court’s interpretation of the Fourth Amendment. Id. To

5
The Fourth Amendment to the U.S. Constitution provides in full:

The right of the people to be secure in their persons, houses, papers, and
effects, against unreasonable searches and seizures, shall not be violated, and no
Warrants shall issue, but upon probable cause, supported by Oath or affirmation,
and particularly describing the place to be searched, and the persons or things to
be seized.

Article I, Section 11 of the Wisconsin Constitution provides in full:

The right of the people to be secure in their persons, houses, papers, and
effects against unreasonable searches and seizures shall not be violated; and no
warrant shall issue but upon probable cause, supported by oath or affirmation,
and particularly describing the place to be searched and the persons or things to
be seized.

7
No. 2025AP503-CR

initiate a lawful traffic stop, a law enforcement officer must have reasonable
suspicion that a traffic law has been, or is being, violated. State v. Houghton,
2015 WI 79, ¶¶29-30, 364 Wis. 2d 234, 868 N.W.2d 143.

¶15 The burden of proving that a traffic stop was reasonable is on the
state. State v. Post, 2007 WI 60, ¶12, 301 Wis. 2d 1, 733 N.W.2d 634. “The
question of what constitutes reasonableness is a common sense test” based on the
totality of the circumstances and what a reasonable police officer would
reasonably suspect in light of his or her training. State v. Anderson, 155 Wis. 2d
77, 83-84, 454 N.W.2d 763; Post, 301 Wis. 2d 1, ¶13. Reasonable suspicion does
not require that an officer rule out possible innocent explanations for the observed
activity prior to conducting a traffic stop “[i]f a reasonable inference of unlawful
conduct can be objectively discerned[.]” State v. Young, 212 Wis. 2d 417, 430,
569 N.W.2d 84 (Ct. App. 1997). However, a mere hunch that a crime is afoot is
not enough, and “‘a particularized and objective basis’” must support the
determination. State v. Nimmer, 2022 WI 47, ¶¶25-26, 402 Wis. 2d 416, 975
N.W.2d 598 (citation omitted). But reasonable suspicion is a low bar, and
“‘considerably less than proof of wrongdoing by a preponderance of the evidence,
and obviously less than is necessary for probable cause.’” Id. (citation omitted).

B. Window Tinting

¶16 A violation of a window tinting administrative code may give rise to
a traffic violation. State v. Bailey, 2009 WI App 140, ¶¶16-18, 321 Wis. 2d 350,
773 N.W.2d 488 (recognizing police officers are authorized to stop vehicles for
administrative code equipment violations). Suspected traffic violations may form
the basis for reasonable suspicion and allow a police officer to conduct a traffic
stop. Houghton, 364 Wis. 2d 234, ¶30; Bailey, 321 Wis. 2d 350, ¶24. Window

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tinting requirements for vehicles are set forth in WIS. ADMIN. CODE
§ Trans 305.32(4)-(6). As noted, the rear window tinting rule, set forth in
§ Trans 305.32(5)(b), permits: (1) manufacturer-applied tinting during the original
manufacturing process with no specified percentage of visible light penetration;
and (2) aftermarket tinting that requires at least 35% of visible light to pass
through the window.6 § Trans 305.32(5)(b); see Conaway, 323 Wis. 2d 250, ¶3
(“Rear window tinting is permitted only if the window allows at least 35% of light
to pass through, except that the limitation does not apply to tinting done during the
original manufacture of a vehicle.”).

¶17 Reasonable suspicion of an aftermarket illegal window tint does not
require a precise determination of the exact percentage of light being transmitted
through a vehicle window. Conaway, 323 Wis. 2d 250, ¶7. “Rather, the officer
need only reasonably suspect that the window violates the [rule].” Id. Indeed, if a
vehicle window appears “at about” the 35% transmission standard set forth in
WIS. ADMIN. CODE § Trans 305.32(5)(b), there is reasonable suspicion that the tint
falls below the acceptable standard. Id.

6
Section 305.32(5)(b) of the Transportation section of the Wisconsin Administrative
Code states, in pertinent part:

(b) Tinting of the rear window is permitted as follows:

1. The window is tinted by the manufacturer of the glazing and is
installed as part of the original manufacturing process.

2. The window is tinted by the application of tinting film to the
inside of the glazing provided that the combination of the glazing
and tinting film permits passage through the window of at least
35% of the visible light striking the window. The tinting films
permitted under this subdivision may not be reflective.

(Emphasis added.)

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No. 2025AP503-CR

¶18 Whether a law enforcement officer had reasonable suspicion to
initiate a traffic stop is a two-step question of constitutional fact. Houghton, 364
Wis. 2d 234, ¶18; see also Tullberg, 359 Wis. 2d 421, ¶27 (whether evidence
should have been suppressed involves a question of constitutional fact). A circuit
court’s findings of historical fact are reviewed for clear error. Tullberg, 359
Wis. 2d 421, ¶27. “A circuit court’s finding of fact is not clearly erroneous unless
it is against the great weight and clear preponderance of the evidence.” State v.
Wiskerchen, 2019 WI 1, ¶17, 385 Wis. 2d 120, 921 N.W.2d 730. Whether a set of
facts, under the totality of the circumstances, constitutes reasonable suspicion is a
legal question I review independently. Tullberg, 359 Wis. 2d 421, ¶27.

C. Stenner’s Car

¶19 The first issue I address is whether Maginot had reasonable
suspicion that the rear window of Stenner’s car violated the rear window tinting
rule. For the reasons set forth, I conclude that Maginot did have reasonable
suspicion that the rear window tint of Stenner’s car violated the rule, justifying the
stop.

¶20 At the time Maginot stopped Stenner’s car, Maginot’s window tint
training was recent, having occurred only weeks prior to the stop. Maginot’s
window tint training taught him that, with the exception of front windshields,
windows on passenger vehicles, such as the car Stenner drove when he was
stopped, are originally manufactured with AS2 glass that allows at least 70% of
light to transmit through the windows. Maginot testified that a window tint with
this percentage of light transmission is not visible to the naked eye. In stopping
Stenner’s car, however, Maginot testified that he could visibly see the tint
covering Stenner’s rear window.

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No. 2025AP503-CR

¶21 Maginot also testified that he is able to identify by sight glass that is
tinted as dark as a windshield band, and that front windshield bands only allow a
percentage of light transmission in the teens or single digit range. Maginot
recognized that Stenner’s rear window tint appeared equivalent to the tint on a
front windshield band, which an officer could reasonably infer therefore violated
the 35% light transmission rule for aftermarket tints. This satisfies the standard set
forth in Conaway, that, when considering the 35% light transmission requirement,
“it would be enough … if an officer testifies that he … is familiar with how dark a
minimally complying window appears and that the suspect window appeared
similarly dark or darker, taking into account the circumstances of the viewing.”
Conaway, 323 Wis. 2d 250, ¶7. Therefore, it was reasonable for Maginot to infer
from these objective facts that the tint on Stenner’s rear window was not applied
by the original manufacturer of the car, but that it was applied as an aftermarket
tint, and that the tint had a lower light transmission percentage than the required
35%.

¶22 To the extent that the circuit court concluded that Maginot lacked
reasonable suspicion for the stop based on his testimony that Stenner’s rear
window was dark, this finding is incomplete. Maginot’s uncontroverted testimony
was that he stopped Stenner’s car because the rear window tint was as dark as a
front windshield band.

¶23 On this point, Stenner argues that Maginot lacked reasonable
suspicion to conduct the traffic stop because Maginot had no way of knowing
whether the rear window tint on Stenner’s car was installed by the manufacturer or
was an aftermarket tint, which was also a finding made by the circuit court in
support of its legal determination that Maginot lacked reasonable suspicion.
However, as stated above, it is reasonable to conclude that Maginot made an

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No. 2025AP503-CR

inference that Stenner’s rear window tint was not installed by the original
manufacturer because the tint was visible and as dark as a front windshield band.
The reasonable suspicion standard does not require that Maginot identify with
absolute certainty that the rear window tint was not applied in the original
manufacturing process, only that Maginot rely on objective facts when reasonably
inferring that it was an aftermarket tint, which Maginot’s testimony supports.

¶24 Moreover, Maginot was not required to determine the precise
percentage of light transparency of Stenner’s rear window tint before developing
reasonable suspicion and initiating the stop. Rather, Maginot need only have
reasonably suspected that Stenner’s rear window tint did not comply with the rear
window tinting rule. Conaway, 323 Wis. 2d 250, ¶7. Indeed, reasonable
suspicion requires only that, under the totality of the circumstances and based on
objective, articulable facts, Maginot reasonably suspected that the rear window
violated the rear window tinting rule. Maginot’s testimony established that this
standard had been met. See id. To the extent that the circuit court based its
determination that Maginot lacked reasonable suspicion on the fact that Maginot
could not precisely determine the percentage of light passing through Stenner’s
rear window in the dark of the early morning, such a determination was not
required to develop reasonable suspicion that Stenner’s car violated the rear
window tinting rule and is an erroneous application of law.

¶25 Although I independently review whether the totality of the facts
support the legal determination of reasonable suspicion, I note that the circuit
court applied the wrong legal standard when it determined that “where there is at
best a 50 percent chance that the law is in fact being violated, the officer does not
have the reasonable suspicion to justify a traffic stop.” This standard was alleged
by Stenner in the circuit court proceedings and in his response brief on appeal, but

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No. 2025AP503-CR

it is not the standard set forth in Stenner’s cited authority nor in the relevant case
law cited in this discussion. See State v. Newer, 2007 WI App 236, ¶8, 306
Wis. 2d 193, 742 N.W.2d 923 (“[T]he reasonable suspicion inquiry considers the
totality of the circumstances.”). Accordingly, the court erred as a matter of law in
applying a “50 percent chance” standard in concluding that Maginot lacked
reasonable suspicion that the rear window tinting rule was violated and did not
have sufficient grounds to initiate the stop.

¶26 Stenner also argues that Maginot’s supposition—that all passenger
vehicles have AS2 glass tinted by the manufacturer to allow 70% of light to
transmit through it—is unreasonable. To underscore this point, Stenner presents
the hypothetical that the rear window of a passenger vehicle with AS2 glass could
be replaced with AS3 glass, which can be tinted during the original manufacturing
process with as dark a tint as desired. I reject this argument because whether AS3
tinted glass “could” be installed in a passenger vehicle is irrelevant to the
reasonable suspicion analysis and overlooks the facts in this case. “Reasonable
suspicion does not require ruling out innocent explanations.” Conaway, 323
Wis. 2d 250, ¶5. Maginot was also not required to affirmatively determine
whether Stenner’s rear window was composed of AS2 or AS3 glass before
conducting the stop. It appears from Maginot’s testimony that the only affirmative
way to determine the type of window glass installed in Stenner’s rear window was
by locating the mylar decal affixed to the window which, based on Maginot’s
testimony, seems to have required stopping Stenner’s car.

¶27 Stenner further argues that Conaway supports the circuit court’s
determination that Maginot lacked reasonable suspicion. Stenner is mistaken.

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No. 2025AP503-CR

¶28 In Conaway, this court affirmed the circuit court’s determination
that the officer did not have reasonable suspicion to make the traffic stop based on
illegal window tinting because the officer failed to connect his training and
experience with the facts of the stop to establish reasonable suspicion. Id., ¶¶8-13
(“[T]he problem is that the officer did not provide any specific, articulable facts
supporting reasonable suspicion of a violation.”). But here, Maginot’s testimony
established the connections between his training about vehicle glass, window tint
and windshield bands, his experience in observing non-tinted windows and the
darkness of windshield bands, and how he applied his training and experience to
his observations of Stenner’s car to develop reasonable suspicion that Stenner’s
rear window violated the rear window tinting rule.

¶29 Stenner also argues that Maginot had only his subjective opinion in
forming reasonable suspicion rather than specific, objective facts, but this
argument fares no better. For the reasons already discussed, I reject it.

¶30 In sum on the issue of reasonable suspicion, I conclude that the
circuit court committed clear error in its pertinent factual findings and applied an
incorrect legal standard in its determination that reasonable suspicion did not exist
to justify the traffic stop. Accordingly, I reverse the circuit court’s decision and
order and remand for further proceedings consistent with this opinion.

II. WISCONSIN ADMIN. CODE § Trans 305.32

¶31 In the alternative, Stenner argues that I should affirm the circuit
court’s decision because the rear window tinting rule, WIS. ADMIN. CODE

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No. 2025AP503-CR

§ Trans 305.32(5)(b)2., is invalid and unenforceable.7 Specifically, Stenner argues
that because the Department of Transportation (“the department”) set a standard in
the rule which is more restrictive than the one contained in the enabling statute for
the rule, which Stenner alleges is WIS. STAT. § 346.88(3), the rear window tinting
rule is invalid. I reject this argument because the department has the authority to
promulgate rules regarding vehicle equipment, which includes window tinting,
and law enforcement may enforce administrative rules on window tinting. See
Bailey, 321 Wis. 2d 350, ¶¶16-18.

¶32 The issue Stenner raises requires me to interpret statutes and
administrative rules. State ex rel. Kalal v. Circuit Ct. for Dane Cnty., 2004 WI
58, ¶46, 271 Wis. 2d 633, 681 N.W.2d 110. The interpretation of statutes and
administrative rules presents a question of law that is reviewed independently.
Wisconsin Ass’n of State Prosecutors (WASP) v. WERC, 2018 WI 17, ¶31, 380
Wis. 2d 1, 907 N.W.2d 425.

¶33 Administrative agencies, including the department, may not
implement or enforce “any standard, requirement, or threshold … unless that
standard, requirement, or threshold is explicitly required or explicitly permitted by
statute or by a rule that has been promulgated in accordance with this
subchapter[.]” WIS. STAT. § 227.10(2m). WISCONSIN STAT. § 227.11(2)(a)
further clarifies that agencies may promulgate rules interpreting the provisions of
any statute enforced or administered by the agency, but “a rule is not valid if the

7
In Stenner’s appellate response brief, he alleges that WIS. ADMIN. CODE
§ Trans 305.32(5)(b)1., which “require[s] minimum levels of light transfer through aftermarket
tinted windows,” is invalid and unenforceable. Because this section pertains to window tint
applied by the original manufacturer of the vehicle, I interpret his argument to be that § Trans
305.32(5)(b)2. is invalid and unenforceable, which is the section that applies to aftermarket tint.

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No. 2025AP503-CR

rule exceeds the bounds of correct interpretation.” § 227.11(2)(a); see also
§ 227.11(2)(a)3. (“A statutory provision containing a specific standard,
requirement, or threshold does not confer on the agency the authority to
promulgate, enforce, or administer a rule that contains a standard, requirement, or
threshold that is more restrictive than the standard, requirement, or threshold
contained in the statutory provision.”).

¶34 To determine whether a statute authorizes an agency to create a rule,
I first conduct a plain language interpretation of the enabling statute to give effect
to the language used therein. Mallo v. DOR, 2002 WI 70, ¶18, 253 Wis. 2d 391,
645 N.W.2d 853. Second, I compare the language in the enabling statute to the
language of the rule. Id., ¶19; WASP, 380 Wis. 2d 1, ¶¶37-39. If the substance of
the rule matches the substance of the language included in the enabling statute,
referred to in case law as “the elements,” the statute authorized the rule. Grafft v.
DNR, 2000 WI App 187, ¶7, 238 Wis. 2d 750, 618 N.W.2d 897. Conversely, if
the rule conflicts with the statute, the rule is invalid. Seider v. O’Connell, 2000
WI 76, ¶¶72-73, 236 Wis. 2d 211, 612 N.W.2d 659. I must strictly construe the
enabling statute because agencies, including the department, may only exercise
those powers which the legislature expressly conferred to it through the statutes
under which the department operates. WASP, 380 Wis. 2d 1, ¶¶37-38; see
Wisconsin Legislature v. Palm, 2020 WI 42, ¶¶51-52, 391 Wis. 2d 497, 942
N.W.2d 900 (explicit authority for rulemaking from the legislature is required
following the codification of WIS. STAT. § 227.10(2m) under 2011 Wis. Act 21).

¶35 On the first point, I conclude that the rear window tinting rule is
explicitly authorized by WIS. STAT. § 110.075. Section 110.075(2) requires motor
vehicles to be subject to inspection “with respect to … glass… and other items of
equipment designated by the secretary” and requires that vehicles meet the

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No. 2025AP503-CR

requirements of WIS. STAT. “ch. 347, or rules issued pursuant thereto” by the
department.8 See also WIS. STAT. § 347.43(1s) (requiring vehicles operated on the
highway to be equipped “with safety glass wherever glass is used on the motor
vehicle in partitions, doors, windows or windshields”). Pursuant to § 110.075(6),
the legislature authorized the department to promulgate rules regarding “the
inspection program,” which includes vehicle glass and windows. See
§ 110.075(6); see also WIS. STAT. § 85.16 (authorizing the department to make
reasonable rules to execute its duties and functions as a department). Moreover, in
WIS. STAT. § 347.02(8), the legislature explicitly anticipated that the department
would establish rules related to window tinting on vehicles and created an
exception to such a rule: “If the department establishes by rule limitations on the
tinting of motor vehicle windows, the limitations do not apply to police vehicles[.]”
(Emphasis added.) Thus, not only did the legislature authorize the department to
promulgate rules about vehicle glass, but the legislature expressly expected that
the department would establish rules on vehicle window tinting and created a
statutory exception.

¶36 As noted, in the second part of the analysis, I compare the language
in the enabling statute to the language in the rule to ensure that the language in the

8
WISCONSIN STAT. § 110.075(2) states in full:

When directed by any traffic officer or motor vehicle inspector, the
operator of any motor vehicle shall stop and submit such motor vehicle to an
inspection and such tests as are necessary to determine whether it meets the
requirements of this section, or that its equipment is not in proper adjustment or
repair, or in violation of the equipment provisions of [WIS. STAT. §§] 110.05,
110.06, 110.063 and 110.064, [WIS. STAT.] ch. 347, or rules issued pursuant
thereto. Such inspection shall be made with respect to the brakes, lights, turn
signals, steering, horns and warning devices, glass, mirrors, exhaust system,
windshield wipers, tires, and other items of equipment designated by the
secretary.

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rule does not exceed the language in the enabling statute. On this second inquiry,
I conclude that the rear window tinting rule, WIS. ADMIN. CODE
§ Trans 305.32(5)(b), does not exceed the language in the enabling statute, WIS.
STAT. § 110.075. The purpose of § Trans 305 “is to prescribe minimum
equipment requirements for vehicles and standards for the equipment used on
vehicles” as authorized by the legislature in § 110.075. § Trans 305.01(1). As
stated, vehicle glass is subject to regulation under § 110.075. The plain language
of § Trans 305.32(5)(b)2. sets a minimum aftermarket tint requirement for a
vehicle’s rear window of permitting “passage through the window of at least 35%
of the visible light striking the window.” Thus, the rule matches the substance of
the language included in the statute. In other words, as authorized by § 110.075,
the rule establishes an aftermarket tinting requirement to allow at least 35% of
light to pass through the vehicle window. “Because the administrative rule neither
contradicts the legislative intent nor exceeds the bounds of correct interpretation,”
I conclude the rule is not invalid or unenforceable. Grafft, 238 Wis. 2d 750, ¶14
(citing Seider, 236 Wis. 2d 211, ¶¶71-72).

¶37 Stenner argues that, in deciding whether the rear window tinting rule
exceeds statutory authority, I should apply the theory of analysis that appears in an
opinion published by then-Attorney General Brad Schimel. Wis. Op. Att’y. Gen.
OAG-04-17 (2017). Attorney general opinions are persuasive, non-binding
authority. State v. Beaver Dam Area Dev. Corp., 2008 WI 90, ¶37, 312 Wis. 2d
84, 752 N.W.2d 295 (“Opinions of the attorney general are not binding as
precedent, but they may be persuasive as to the meaning of statutes.”). I reject
Stenner’s argument because the analytical method set forth in the Attorney
General opinion was withdrawn in an opinion published by current-Attorney
General Josh Kaul. Wis. Op. Att’y. Gen. OAG-04-20, ¶¶5, 27 (2020). Stenner

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identifies no supporting legal authority for the proposition that a withdrawn
Attorney General opinion has persuasive value, and I reject his argument on this
point. See State v. Pettit, 171 Wis. 2d 627, 646-47, 492 N.W.2d 633 (Ct. App.
1992) (a court need not consider arguments that are unsupported by legal citations
or are otherwise undeveloped).

¶38 Stenner also argues that the only possible enabling statute for the
rear window tinting rule is WIS. STAT. § 346.88(3), which he states does not
support the rule. Section 346.88(3) prohibits the obstruction of the driver’s view
of a vehicle’s front and rear windshields with stickers or other objects.9 Stenner’s
argument fails because, as discussed, § 346.88 is not the only enabling statute for
the rear window tinting rule. I additionally reject this argument because
§ 346.88(3)(a) prohibits “nontransparent material” on rear windows. The purpose

9
WISCONSIN STAT. § 346.88(3) states, in pertinent part:

(a) No person shall drive any motor vehicle with any sign, poster
or other nontransparent material upon the front windshield, front
side wings, side windows in the driver’s compartment or rear
window of such vehicle other than a certificate or other sticker
issued by order of a governmental agency. Such permitted
sticker shall not cover more than 15 square inches of glass
surface and shall be placed in the lower left-hand corner of the
windshield; the left corner being on the driver’s left when seated
behind the wheel.

(b) No person shall drive any motor vehicle upon a highway
with any object so placed or suspended in or upon the vehicle so
as to obstruct the driver’s clear view through the front
windshield.

(c) No person shall drive any motor vehicle upon a highway so
loaded or with any object so placed or suspended in or upon the
vehicle so as to obstruct the driver’s clear vision through the rear
window unless such vehicle is equipped with an outside rear
view mirror meeting the requirements of [WIS. STAT. §] 347.40.

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No. 2025AP503-CR

of window tinting is to make the window less or nontransparent. As such, this
statute also provides a basis, when combined with the other statutes, for the
department to promulgate the rear window tinting rule.

¶39 In sum on this issue, I reject Stenner’s argument that the rear
window tinting rule is invalid and unenforceable.

CONCLUSION

¶40 For the reasons set forth above, I reverse the circuit court’s order
granting Stenner’s motion to suppress and remand for further proceedings
consistent with this opinion.

By the Court.—Order reversed and cause remanded for further
proceedings.

This opinion will not be published. See WIS. STAT.
RULE 809.23(1)(b)4.

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