delivered the judgment of the court, with opinion.
Chief Justice Kilbride and Justices Thomas and Gar-man concurred in the judgment and opinion.
Justice Freeman dissented, with opinion, joined by Justices Burke and Theis.
OPINION
After a lawful traffic stop, a police officer performed a set-up procedure, which entailed ordering the driver, defendant, Cheryl L. Bartelt, to roll up her truck’s windows and turn the ventilation system’s blowers on high before a second officer conducted a canine sniff of the exterior of her truck. The dog alerted on both doors of the truck, and a subsequent search of the truck resulted in discovery of drug evidence. Defendant was arrested and charged with unlawful possession of methamphetamine (720 ILCS 646/60(b)(l) (West 2006)). She filed a motion to suppress the evidence recovered during the traffic stop. The circuit court of Adams County granted the motion to suppress. The State filed an interlocutory appeal pursuant to Illinois Supreme Court Rule 604(a)(1) (eff. July 1, 2006). A majority of the appellate court reversed the circuit court’s order suppressing the evidence. 384 Ill. App. 3d 1028. This appeal followed.
We are asked to determine whether the officers’ actions in ordering defendant to roll up her windows and turn the blowers on high before conducting a dog sniff of the truck’s exterior constituted an unreasonable search under the fourth amendment. We hold that it did not. Accordingly, we affirm the judgment of the appellate court, reverse the judgment of the circuit court, and remand to the circuit court for further proceedings consistent with this opinion.
BACKGROUND
The evidence introduced at the hearing on the motion to suppress can be summarized as follows. On the evening of July 29, 2006, Quincy police officer Mike Tyler, who had received information that defendant was a methamphetamine user, conducted surveillance of her apartment. At 6:45 p.m., he saw a pickup truck parked on the sidewalk in front of her apartment, ran the plates, and learned the truck was registered to her. At 8:15 p.m., he saw her and a man, later identified as Josh Miracle, come out of the apartment and place white trash bags in the back of the truck. Defendant got in the driver’s seat and Miracle in the passenger seat. Defendant drove away, and Officer Tyler followed. He then alerted Quincy police officer Darin Kent, a member of the canine unit, that he intended to make a traffic stop and asked Officer Kent to conduct a dog sniff during the stop. Officer Tyler activated his lights when defendant pulled into a nearby gas station. He radioed Officer Kent that he had made the stop and provided the location.
Officer Tyler then approached defendant’s truck and told her that she had violated the Illinois Vehicle Code by parking her truck on the sidewalk in front of her apartment for over an hour and a half. He asked for and obtained her driver’s license and insurance information and returned to his squad car to conduct a computer check of this information. However, within approximately 20 seconds after he returned to his car, and within three minutes of the initial stop, Officer Kent arrived at the scene with his narcotics detection dog, Max.
Officer Kent is a certified canine handler for the department’s street crimes unit. He follows the format for dog sniffs taught by the Illinois State Police canine unit and taught his fellow officers to follow the same procedures. One such procedure is a set-up procedure, which is done before the dog is taken around the vehicle. The set-up procedure entails telling the driver to turn off the engine; turn the key on auxiliary, which allows the blowers to work; turn the blowers on high; roll up the windows; and close the doors. The purpose of the set-up procedure is to force air inside the vehicle out through the seams, where the dogs are trained to sniff.
Officer Kent asked Officer Tyler to set up defendant’s truck for the dog sniff. Officer Tyler reapproached defendant, who was sitting in her truck, and told her to roll up her windows and turn the blowers on high. She complied, and Officer Kent conducted the dog sniff.
Officer Kent begins a dog sniff by walking the dog parallel to the vehicle, beginning at the front and proceeding counterclockwise for two passes. The dog signals an alert by turning perpendicular to the vehicle. In addition, the dog’s breathing will change, and his sniffing will intensify or become more rapid. Finally, the dog will put a paw out, look at the handler, and start barking. Probable cause is obtained through a dog’s positive alert.
Officer Tyler had returned to his squad car to run defendant’s information but had not started writing the ticket when Officer Kent informed him that Max had alerted on both doors of the truck. Officer Tyler went back to defendant’s truck and told her and Miracle to exit the truck. The officers obtained consent from both defendant and Miracle to search their persons. Nothing was found.
A subsequent search of the truck and defendant’s purse, which was inside, revealed a bag containing a digital scale with white powder residue; several burnt pieces of tinfoil; and a pen casing, with a burnt end and a powder substance on the inside. Defendant was arrested and charged with unlawful possession of methamphetamine (720 ILCS 646/60(b)(l) (West 2006)).
Defendant filed a motion to suppress the evidence recovered during the traffic stop. During argument on the motion, defense counsel stated that before the hearing, he was unaware that a set-up procedure was used to facilitate the dog sniff. Therefore, in his suppression motion, counsel had argued that Officer Tyler’s stop of defendant was an illegal seizure because he had manipulated the timing of the traffic stop by waiting for defendant to get into her truck and drive off, instead of knocking on the door of her apartment and issuing her a citation. Counsel had also focused on Officer Tyler’s admission that he had intended to search the truck, hoping to find more incriminating evidence.
The circuit court rejected defendant’s argument regarding Officer Tyler’s motivation. However, the court found the set-up procedure more interesting, noting that this was the first instance the court, the prosecutor, or defense counsel had encountered such a procedure. Because the court was curious as to whether the officers had the authority to direct defendant to roll up her windows and turn the blowers on high, it continued the matter to allow briefing on the issue.
When the hearing resumed, the parties informed the court that they agreed that the United States Supreme Court’s decision in Illinois v. Caballes, 543 U.S. 405 (2005), authorizes police to conduct a dog sniff and that a dog sniff ordinarily is not a search. They also agreed that there was no undue delay occasioned by the dog sniff, and no one disputed Max’s qualification to perform the dog sniff.
The parties disagreed, however, as to whether the officers had the authority to order defendant to comply with the set-up procedure before conducting the dog sniff. Although the propriety of the set-up procedure appeared to be a matter of first impression in Illinois, the State cited to United States v. Ladeaux, 454 F.3d 1107 (10th Cir. 2006), as being factually analogous, to the extent that the defendant challenged the validity of the use of a set-up procedure identical to that employed here during a routine traffic stop. However, although the circuit court and the parties discussed United States v. Ladeaux’s focus on whether police mandated compliance with the procedure — which would render it an additional seizure— they noted that the Tenth Circuit had remanded the cause to the district court for this determination and that the results had not yet been reported.
As an outgrowth of this discussion, the State conceded that because Officer Tyler could not recall exactly how he phrased his statement to roll up the windows and turn on the blowers, and given that Officer Kent testified that he instructed his fellow officers not to give motorists a choice of complying, the court could assume that Officer Tyler told defendant to do it. Nevertheless, the State contended that this was not controlling, asserting that because the set-up procedure is a minimally intrusive, “recognized method of instruction,” it did not violate the fourth amendment.
The circuit court granted defendant’s motion to suppress. Initially, the court found that the traffic stop was justified based on defendant’s violation of the Illinois Vehicle Code. In addition, the court found that the stop was not unreasonably extended by the calling of the canine unit to the scene. The court stated that the issue was whether defendant’s fourth amendment rights were violated by the officers instructing her to roll up her windows and turn the blowers on high. The circuit court held that the officers had no probable cause to search the truck before Max alerted.
The circuit court found Illinois v. Caballes distinguishable because, in that case, the dog sniff occurred on the exterior of the vehicle. In the present case, although Max alerted from the outside of defendant’s truck, he “had some help” in that the “air from the interior was being forced out of the truck by the turned-up blowers,” and “[t]he blowers were turned up by the defendant, but only upon the demand of the officers.” The court concluded that by requiring defendant to roll up the windows and turn the blowers on high, the officers, in effect, moved and manipulated the air within the truck that would not otherwise have been subject to Max’s plain smell. Although the court recognized that Max was still outside defendant’s truck when he alerted, the court found that, in effect, Max was placed inside the truck by the officers. The circuit court concluded that directing defendant to roll up her windows and turn the blowers on high turned the dog sniff into an unreasonable search under the fourth amendment.
The State filed an interlocutory appeal. The State argued that the circuit court’s decision should be reversed because the officers’ orders to roll up the windows and turn the blowers on high did not change the nature of the dog sniff to an unlawful search because (1) Max remained outside the truck and (2) defendant had no legitimate expectation of privacy in the potentially incriminating odors emanating from her lawfully stopped truck.
Initially, the appellate court noted that the arguments on appeal were limited to the set-up procedure employed by the officers before the dog sniff and that no other portion of the stop was at issue. 384 Ill. App. 3d at 1031. The appellate court stated the issue as “whether the police order to defendant to roll up her windows and turn the blower to high intruded upon a legitimate privacy interest and constituted a search under the fourth amendment.” Id. at 1031-32.
A divided appellate court reversed the circuit court’s suppression order. Id. at 1036. Upholding the validity of the set-up procedure, the majority found it “to be a practical tool of police work that does not interfere with the reasonable expectation of privacy in the interior of defendant’s [truck].” Id. at 1035. The appellate court noted that, under Illinois v. Caballes, a dog sniff conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no one has the right to possess does not violate the fourth amendment. Id. The appellate court concluded as follows:
“The set-up procedure is quick and nonintrusive; thus, it does not impermissibly lengthen the duration of the stop. It also ensures the canine remains outside the vehicle during the sniff, as both the doors and windows are closed. This is a practical technique that balances a defendant’s reasonable expectation of privacy with the opportunity to allow law enforcement to ferret out crime. No fourth-amendment violation occurs when an officer lawfully investigating a traffic violation orders the occupant to roll up the windows and turn on the blowers to facilitate a dog sniff.” Id. at 1035-36.
The dissenting justice would have affirmed the circuit court’s suppression order, concluding as follows:
“ ‘Plain view’ includes items that would be within the ‘plain smell’ of a dog at the exterior of a vehicle. In the present case, the officer impermissibly went beyond what was in plain view and ordered the occupants of the vehicle to engage in testing.” Id. at 1036 (Cook, J., dissenting).
This court allowed defendant’s petition for leave to appeal. Ill. S. Ct. R. 315 (eff. Feb. 26, 2010).
ANALYSIS
The fourth amendment to the United States Constitution protects the “right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures.” U.S. Const., amend. IV; accord Ill. Const. 1970, art. I, §6.1 Thus, the guarantees of the fourth amendment attach where a “search” or “seizure” takes place. “A ‘search’ occurs when an expectation of privacy that society is prepared to consider reasonable is infringed.” United States v. Jacobsen, 466 U.S. 109, 113 (1984). In contrast, a “seizure” occurs when “the police conduct would have communicated to a reasonable person that the person was not free to decline the officers’ requests or otherwise terminate the encounter.” Florida v. Bostick, 501 U.S. 429, 439 (1991).
A circuit court’s ruling on a motion to suppress evidence is reviewed under the two-part test adopted by the Supreme Court in Ornelas v. United States, 517 U.S. 690, 699 (1996). People v. Harris, 228 Ill. 2d 222, 230 (2008). The circuit court’s factual findings may be rejected only if they are against the manifest weight of the evidence. Id. However, the reviewing court may assess the established facts in relation to the issues presented and may draw its own conclusions in deciding what relief, if any, should be granted. Id. Accordingly, the circuit court’s ultimate ruling as to whether suppression is warranted is reviewed de novo. Id.
The issue presented in this appeal is narrow. There is no dispute regarding the circuit court’s factual finding that the initial traffic stop was justified by Officer Tyler’s observation of defendant’s violation of the Illinois Vehicle Code (625 ILCS 5/11 — 1303(a)(1)(b) (West 2006) (no person shall stop, stand, or park a vehicle on a sidewalk)), and that the seizure, therefore, was reasonable. See Whren v. United States, 517 U.S. 806, 810 (1996) (“[T]he decision to stop an automobile is reasonable where the police have probable cause to believe that a traffic violation has occurred.”).
In addition, it is undisputed that the officers had the authority to conduct an exterior dog sniff of defendant’s truck during the traffic stop and that the dog sniff itself was not a search subject to the fourth amendment. See Illinois v. Caballes, 543 U.S. at 408-10 (holding that a suspicionless dog sniff conducted during a lawful traffic stop that reveals no information other than the location of a substance no individual has any right to possess is not a search subject to the fourth amendment).
Finally, there is no dispute that Officer Tyler ordered defendant to comply with the set-up procedure. As noted, the State conceded in the circuit court that Officer Tyler ordered defendant to perform the procedure and did not give her the option of refusing to comply.
The only issue on appeal is whether the officers’ actions in ordering defendant to roll up her windows and turn the blowers on high before conducting the dog sniff of the truck’s exterior constituted an unreasonable search under the fourth amendment. This seems to be an issue of first impression nationwide because the parties have not cited, nor has our research revealed, any decisions that have addressed the issue.
The dissent would like us to recharacterize the issue as whether the officers’ actions in ordering defendant to roll up her windows and turn the blowers on high before conducting the dog sniff of the truck’s exterior constituted an unreasonable seizure under the fourth amendment. We decline to do so because it is clear that, in her briefs and oral arguments before this court, defendant argues that the officers’ actions in ordering her to roll up her windows and turn the blowers on high before conducting the dog sniff of the truck’s exterior constituted an unreasonable search, not an unreasonable seizure.
For example, in the “General Principles” portion of her brief, defendant includes exclusively fourth amendment search principles. She explains that “[a] search for purposes of the [fjourth [ajmendment occurs when government officials violate an individual’s legitimate expectation of privacy.” Appellant’s Br. 18. She sets forth general “expectation of privacy” principles and explains what level of privacy can reasonably be expected in relation to an automobile. Appellant’s Br. 18-21. She states that “[a]t issue here is whether the police ‘set up’ procedure created an unreasonable search under the fourth amendment.” (Emphasis added.) Appellant’s Br. 20-21. Notably, she does not explain when a “seizure” occurs for purposes of the fourth amendment.
Similarly, the “Analysis” section of her brief is devoted exclusively to whether the set-up procedure resulted in an unconstitutional search of the interior of her truck. She devotes her entire discussion to fourth amendment search cases and to arguing that (1) she had a reasonable expectation of privacy in the interior of her truck and that (2) the set-up procedure therefore resulted in an unconstitutional search of her truck. Even her brief discussion of United States v. Ladeaux leads her to conclude that “[t]he resulting sniff thus became a search subject to the fourth amendment.” (Emphasis added.) Appellant’s Br. 22. She did not argue that the officer’s order to roll up the windows and turn the blowers on high amounted to a seizure for fourth amendment purposes — that is, that the order communicated to her that she was not free to decline the request or otherwise terminate the encounter. See Bostick, 501 U.S. at 439.
Although she asserts in the very last paragraph of the “Analysis” section of her brief that “Officer Tyler impermissibly acted by turning the traffic stop into an illegal seizure by ordering [her] to place the vehicle on auxiliary power, to turn the vents to high, and to keep all doors and windows closed” (appellant’s br. 27), she offers no support for that assertion, either factually or legally. In fact; the only authority that she cites in support of that assertion is the United States Supreme Court’s pronouncement in Horton v. California, 496 U.S. 128 (1990), that “a ‘search’ compromises an individual interest in privacy.” (Emphasis added.) Appellant’s Br. 27. Even here, then, she is making a search argument. Reading the paragraph as a whole, and given that her sole citation is to a fourth amendment search principle, we assume that what she is attempting to argue is that, as a result of the unlawful search, the otherwise lawful seizure was transformed into an unlawful seizure. This is very different from the seizure argument addressed in the dissent.
The final section of the State’s brief is titled “Defendant Makes No Argument That The Set-Up Procedure Was A Seizure.” Appellee’s Br. 26. This section is a direct response to the isolated sentence described above, and the State obviously included it to avoid any possibility that this court would use that sentence as a basis for treating this as a seizure case rather than a search case. Notably, in her reply brief, defendant does not contest or even respond to this argument, offering instead only the same “expectation of privacy” and “search” arguments that she offered in her opening brief. While not binding, such silence certainly underscores what is otherwise apparent — that defendant is not arguing that the orders relating to the set-up procedure amounted to an unlawful seizure.
Finally, at oral argument before this court, defense counsel made it abundantly clear that defendant’s argument is that the set-up procedure was an unlawful search, not an unlawful seizure. Accordingly, we confine our analysis to defendant’s search argument and save the seizure analysis for a case where the issue is properly before us and has been fully briefed and argued.
As stated previously, “[a] ‘search’ occurs when an expectation of privacy that society is prepared to consider reasonable is infringed.” Jacobsen, 466 U.S. at 113. Consequently, “[o]fficial conduct that does not ‘compromise any legitimate interest in privacy’ is not a search subject to the Fourth Amendment.” Caballes, 543 U.S. at 408 (quoting Jacobsen, 466 U.S. at 123).
The Supreme Court has held that “any interest in possessing contraband cannot be deemed ‘legitimate,’ and thus, governmental conduct that only reveals the possession of contraband ‘compromises no legitimate privacy interest.’ ” Id. (quoting Jacobsen, 466 U.S. at 123). The Court explained that “the expectation ‘that certain facts will not come to the attention of the authorities’ is not the same as an interest in ‘privacy that society is prepared to consider reasonable.’ ” Id. at 408-09 (quoting Jacobsen, 466 U.S. at 122). The Court noted that, in United States v. Place, 462 U.S. 696 (1983), it “treated a canine sniff by a well-trained narcotics-detection dog as ‘sui generis’ because it ‘discloses only the presence or absence of narcotics, a contraband item.’ ” Caballes, 543 U.S. at 409 (quoting Place, 462 U.S. at 707).
In Illinois v. Caballes, the Court held that “the use of a well-trained narcotics-detection dog — one that ‘does not expose non-contraband items that otherwise would remain hidden from public view,’ [citation] — during a lawful traffic stop generally does not implicate legitimate privacy interests.” Id. The Court explained:
“In this case, the dog sniff was performed on the exterior of respondent’s car while he was lawfully seized for a traffic violation. Any intrusion on respondent’s privacy expectations does not rise to the level of a constitutionally cognizable infringement.
*** A dog sniff conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no individual has any right to possess does not violate the Fourth Amendment.” Caballes, 543 U.S. at 409-10.
Similarly, in the present case, the dog sniff was conducted on the exterior of defendant’s truck while she was lawfully seized for a traffic violation. Even though the officers ordered her to roll up her windows and turn the blowers on high before they conducted the dog sniff, any intrusion on her “privacy expectations does not rise to the level of a constitutionally cognizable infringement.” See id. at 409. The dog sniff revealed “no information other than the location of a substance that no individual has any right to possess.” See id. at 410. Accordingly, under Illinois v. Caballes, the dog sniff in the present case was not a search subject to the fourth amendment because it did not “ ‘compromise any legitimate interest in privacy.’ ” See id. at 408 (quoting Jacobsen, 466 U.S. at 123).
The set-up procedure at issue in this case is analogous to the luggage “prepping” procedure approved by the Fifth Circuit in United States v. Viera, 644 F.2d 509 (5th Cir. 1981). In United States v. Viera, Drug Enforcement Administration agents “prepped” the defendants’ suitcases before a dog sniff by pressing them lightly with the hands and slowly circulating the air, the purpose of which was to procure a scent from the bags. Viera, 644 F.2d at 510. The Fifth Circuit rejected the defendants’ argument that the “prepping” procedure was a search in violation of the fourth amendment, holding that a dog sniff is not a search within the meaning of the fourth amendment and that a light press of the hands along the outside of the suitcases was not sufficiently intrusive to require a different result. Id.
Similarly, in the present case, a dog sniff is not a search within the meaning of the fourth amendment, and ordering defendant to roll up her windows and turn the blowers on high before conducting the dog sniff was not sufficiently intrusive to require a different result. See id.
CONCLUSION
For the foregoing reasons, the judgment of the appellate court is affirmed.
Affirmed.
Defendant limits her argument to the fourth amendment to the United States Constitution (U.S. Const., amend. IV) and does not contend that the search and seizure provision of article I, section 6, of the Illinois Constitution (Ill. Const. 1970, art. I, §6) provides broader protection than the fourth amendment. Accordingly, we confine our analysis to defendant’s fourth amendment claim.