dissenting: Ronnie Morlock, a passenger in a van he had rented, claims that his Fourth Amendment rights were violated when an officer did no more than ask a handful of questions about travel plans, ask him for an ID, take the ID back briefly to a patrol car, and check by radio for outstanding warrants. Morlock concedes *237that the traffic stop itself was proper, so his claim rests on the premise that an officer may not ask about travel plans or ask a passenger for ID and conduct a warrant check during a normal traffic stop. But Morlock’s claim about the warrant check is precluded by recent United States Supreme Court cases interpreting the Fourth Amendment — cases that we are required to follow. And his claim that the officer couldn’t ask limited questions about his travel plans is contrary both to the rationale of recent United States Supreme Court cases and to cases decided by courts elsewhere.
Moreover, even if the officer did something not allowed in a typical vehicle stop, that action would not be cause to suppress the evidence of 113 pounds of marijuana found in Morlock’s van. First, the district court properly found that the officer had reasonable suspicion based on the evidence, and reasonable suspicion allows an officer to detain someone briefly to investigate possible criminal activity. Second, the officer’s mistake didn’t have any coercive impact on Morlock. Morlock’s consent came after the officer had given sufficient indication that Morlock was free to leave by returning all paperwork, saying, “Have a nice day,” and taking a couple of steps to leave. Thus, when the officer returned and asked whether Morlock would agree to talk further, Morlock’s agreement — and his later agreement that the officer could search the van — was voluntary. As the search was voluntary, we shouldn’t suppress the evidence against Morlock and set aside his conviction.
I. Recent United States Supreme Court Cases Dictate That an Officer May Ask for a Passengers ID and Run a Warrant Check During a Traffic Stop.
The first issue is whether the officer could ask Morlock for his ID and then check for arrest warrants against him. Two key Supreme Court cases both involve traffic stops: Illinois v. Harris, 543 U.S. 1135, 161 L. Ed. 2d 94, 125 S. Ct. 1292 (2005); and Illinois v. Caballes, 543 U.S. 405, 160 L. Ed. 2d 842, 125 S. Ct. 834 (2005). Harris, like our case, involved an officer asking a passenger for ID and running a warrant check on him. We can’t say with certainty what the United States Supreme Court thought about that specific factual situation because the Court didn’t issue an opinion. Instead, *238the Court vacated the Illinois Supreme Court’s decision that the officer had violated the Fourth Amendment, and the Court told the Illinois Supreme Court to reconsider its Harris decision “in light of’ Caballes. So it would seem that Caballes may hold the key to our case as well.
The Illinois Supreme Court found that Caballes was the key to its case. And based on Caballes, the Illinois Supreme Court reversed its prior decision and concluded earlier this year that asking a passenger for ID and running a warrant check on the passenger did not violate the Fourth Amendment. People v. Harris, 228 Ill. 2d 222, 886 N.E.2d 947 (2008). To facilitate discussion of both the original Illinois decision, People v. Harris, 207 Ill. 2d 515, 802 N.E.2d 219 (2003), which found a Fourth Amendment violation, and the more recent decision, which did not find a violation, I will refer to the 2003 decision as Harris I and the 2008 decision as Harris II.
To put matters in context, we must start with Harris I. In it, the Illinois Supreme Court applied what it viewed as well-established rules for traffic stops. It applied its own cases interpreting Terry v. Ohio, 392 U.S. 1, 20 L. Ed. 2d 889, 88 S. Ct. 1868 (1968), which governs how police may detain someone to investigate possible wrongdoing. Under a Terry stop, the Illinois court noted that the officer’s actions must be “reasonably related in scope to the circumstances which justified the interference” with the person’s freedom. 207 Ill. 2d at 523. The court concluded that running a warrant check on the passenger “was impermissible because it changed the fundamental nature of the traffic stop,” converting it “from a routine traffic stop into an investigation of past wrongdoing by [the passenger].” 207 Ill. 2d at 528. A warrant check on the passenger could be done only if the officer had reasonable suspicion that the passenger had committed a crime. 207 Ill. 2d at 530-31.
But that decision did not stand. The United States Supreme Court set it aside and ordered reconsideration based on Caballes. Before considering Harris II, tiren, we should consider Caballes.
Caballes had seemed like an easy case for the Illinois Supreme Court. Its opinion began with a familiar review of Terry stop rules, *239noting that the State had the burden to show “that the conduct remained within the scope of the stop.” People v. Caballes, 207 Ill. 2d 504, 509, 802 N.E.2d 202 (2003). A trooper stopped a driver for speeding on an interstate highway. During the stop, a drug-interdiction team came to the scene. A police dog walked around the car; the dog alerted, and drugs were found. The legal issue seemed simple enough. The driver was stopped for speeding, but the police conducted an investigation for drugs. Was that within the scope of the stop? The Illinois court said no: “the police impermissibly broadened the scope of the traffic stop . . . into a drug investigation.” The police could only broaden the scope with reasonable suspicion of drug activity. 207 Ill. 2d at 509.
But that decision did not stand, either. In a six to two decision (one justice not participating), the United States Supreme Court reversed Illinois’ holding in Caballes. The Court said that a traffic stop could “become unlawful if it is prolonged beyond the time reasonably required to complete that mission,” 543 U.S. at 407, but it accepted the state court’s conclusion “that the duration of the stop in this case was entirely justified by the traffic offense and the ordinary inquiries incident to such a stop.” 543 U.S. at 408. For Fourth Amendment purposes, the Court next concluded that “conducting a dog sniff would not change the character” of a lawful traffic stop “unless the dog sniff itself infringed [upon the defendant’s] constitutionally protected interest in privacy.” 543 U.S. at 408. The Court noted that prior cases had decided that there was no legitimate interest in possessing illegal drugs, so “governmental conduct that only reveals the possession of contraband 'compromises no legitimate privacy interest.’ ” 543 U.S. at 408. In sum, so long as the police officer during a lawful traffic stop does nothing further beyond that stop to invade protected interests, the stop remains legal even though some of the officer’s actions do not directly relate to the reason for the stop. If this were not the message of Caballes, how else could an officer bring in a drug dog— obviously unrelated to the reason for the stop — during a traffic stop for speeding?
The Illinois Supreme Court had to determine the meaning of Caballes in Harris II. The court considered the Supreme Court’s *240directive to consider the case “in light of Caballes” to mean that it should “conduct the same type of inquiry that [the Supreme Court] applied to dog sniffs to determine whether a warrant check performed during a concededly lawful traffic stop compromises a constitutionally protected interest by revealing legitimately private information.” 228 Ill. 2d at 235. Because a warrant for a person’s arrest “is a matter of public record,” the person “has no reasonable expectation of privacy in [that] fact.” 228 Ill. 2d at 237. Thus, the Illinois court concluded that a warrant check on a passenger during a traffic stop did not violate the Fourth Amendment: “like a dog sniff, it does not reveal any legitimately private activity or information, or result in any physical contact with the individual or his property.” 228 Ill. 2d at 237. As a general rule, the court concluded that “so long as the duration of the stop is not unnecessarily prolonged for the purpose of conducting the check” and the stop was otherwise lawful, “a warrant check on the occupants of a lawfully stopped vehicle” does not violate the Fourth Amendment. 228 Ill. 2d at 237.
The Illinois court also considered whether its old test for the propriety of a car stop — under which both the duration and the scope of the stop are limited — remained valid after Caballes. The court determined that it could not answer that question based on Caballes alone but that Caballes in combination with Muehler v. Mena, 544 U.S. 93, 161 L. Ed. 2d 299, 125 S. Ct. 1465 (2005), provided the answer. In Muehler, the Court held that law-enforcement officers could ask questions unrelated to the purpose of a search when executing a search warrant in a private residence — -as long as it didn’t prolong the search. The Muehler Court noted that “ ‘mere police questioning does not constitute a seizure.’ ” 544 U.S. at 101 (quoting Florida v. Bostick, 501 U.S. 429, 434, 115 L. Ed. 2d 389, 111 S. Ct. 2382 [1991]). The Court concluded that the officer “did not need reasonable suspicion to ask Mena for her name, date and place of birth, or immigration status.” 544 U.S. at 101. The Illinois court noted that in both Muehler and Caballes, the Court had allowed questioning unrelated to the purpose of the encounter while a person was subject to a lawful seizure:
*241“In light of Muehler, it becomes clear that Caballes rejected reasoning that led to this court’s adoption of the ‘fundamental alteration of the nature of the stop’ portion of the ‘scope’ prong of [our former test]. All that remains is the duration prong. During a lawful seizure, as occurred in both Muehler and Caballes, the police may ask questions unrelated to the original detention and are not required to form an independent reasonable suspicion of criminal activity before doing so. Further, die Court’s reliance on Bostick in Muehler indicates that the encounter should be analyzed under Bostick, even when the person being questioned has already been seized. [Citation omitted.]” 228 Ill. 2d at 242-43.
The Illinois court’s reading of Caballes and Muehler is consistent with that of other courts. Relying on Caballes or Muehler or both, at least six federal circuit courts of appeal and state appellate courts in five other states have concluded that an officer may ask questions during a traffic stop that don’t relate to the purpose of the stop so long as the duration of the stop is not appreciably extended. See United States v. Soriano-Jarquin, 492 F.3d 495, 501 (4th Cir. 2007); United States v. Martin, 422 F.3d 597, 600 (7th Cir. 2005); United States v. Olivera-Mendez, 484 F.3d 505, 510 (8th Cir. 2007); United States v. Mendez, 476 F.3d 1077, 1080 (9th Cir. 2007); United States v. Stewart, 473 F.3d 1265, 1267, 1269 (10th Cir. 2007); United States v. Hernandez, 418 F.3d 1206, 1209 n.3 (11th Cir. 2005); People v. Johnson, 2007 WL 4447306, at *3 (Cal. App. 2007); Salmeron v. State, 280 Ga. 735, 736-39, 632 S.E.2d 645 (2006); State v. Stewart, 145 Idaho 641, 646-47, 181 P.3d 1249 (2008); Pearson v. State, 870 N.E.2d 1061, 1066 (Ind. App. 2007); Com. v. Briggs, 2006 WL 850667, at *4 (Va. App. 2006) (unpublished opinion); Marinaro v. State, 163 P.3d 833, 835 (Wyo. 2007). In Soriano-Jarquin, the Fourth Circuit specifically addressed whether an officer could ask a passenger for identification and concluded that asking a passenger for identification during a traffic stop did not violate the Fourth Amendment when it did not prolong the stop, citing Muehler. 492 F.3d at 501. In addition, the Alaska Court of Appeals agreed that the Supreme Court’s recent decisions left no Fourth Amendment bar to questions unrelated to the reason for a traffic stop; it proceeded to interpret its state’s constitutional prohibition on search and seizure more broadly. Brown v. State, 182 P.3d 624, 628-34 (Alaska App. 2008).
*242Surely among the questions that may be asked are, “Who are you?” and “Could I see your ID, please?” The Supreme Court has said so: “In the ordinary course a police officer is free to ask a person for identification without implicating the Fourth Amendment.” Hiibel v. Sixth Judicial Dist. Court of Nev., Humboldt Cty., 542 U.S. 177, 185, 159 L. Ed. 2d 292, 124 S. Ct. 2451 (2004); see also INS v. Delgado, 466 U.S. 210, 216, 80 L. Ed. 2d 247, 104 S. Ct. 1758 (1984) (“[I]nterrogation relating to one’s identity or a request for identification by the police does not, by itself, constitute a Fourth Amendment seizure.”); United States v. Diaz-Castaneda, 494 F.3d 1146 (9th Cir.) (held it was proper to ask a passenger for ID while detained, citing Hiibel), cert. denied 169 L. Ed. 2d 410 (2007). In Bostick, a case in which police boarded a bus and questioned its passengers, the Court said that “even when officers have no basis for suspecting a particular individual, they may generally ask questions of that individual, ask to examine the individual’s identification, and request consent to search his or her luggage. [Citations omitted.]” 501 U.S. at 434-35. If the officer may “ask to examine” the ID, surely the officer may follow up by actually examining it.
So the Illinois Supreme Court’s decision in Harris II is on solid ground. An officer may ask a passenger for ID and may examine it. With the ID in hand, the officer may check for warrants as an individual has no more of a privacy interest in public records of arrest warrants than he would in contraband in a car trunk. And the Supreme Court has confirmed that the issue of whether an officer may get a passenger’s ID and check for warrants should be based on Caballes. That Court vacated the decision in Hanis I, which found that checking a passenger’s ID for warrants violated the Fourth Amendment. And that Court told the Illinois Supreme Court to reconsider the matter “in light of’ Caballes. Based upon the United States Supreme Court’s interpretation of the Fourth Amendment, an officer may ask a passenger for ID and run a warrant check on the passenger as long as that does not substantially extend the duration of the traffic stop.
The duration of this stop was not extended substantially by asking for Morlock’s ID and checking for warrants on him. The officer *243began the stop by approaching Morlock’s son, Ronald O’Kelly, who was driving. After talking with O’Kelly, the officer spoke with Morlock. The officer then took the rental agreement and the parties’ licenses back to his patrol car. Up to this point, the duration of the traffic stop was less than 3 minutes. The officer then walked back to his patrol car, wrote a warning citation for O’Kelly, and ran both names through a warrant check. The officer returned to the stopped car about 8Vz minutes after he had left. Within moments, he handed the documents back to Morlock, stepped back, and said, “Have a nice day.” In total, the traffic stop took about 12 minutes to that point. Within those 12 minutes, die time needed to take Morlock’s ID and run his warrant check was negligible as O’Kelly was being checked too.
The United States Court of Appeals for the Tenth Circuit has found traffic stops of up to 19 minutes within a reasonable duration under the Fourth Amendment. E.g., United States v. Patterson, 472 F.3d 767, 776-77 (10th Cir. 2006) (a traffic stop of 13 minutes for the officer to ask the driver and the passenger about their travel plans, explain speeding infraction, check license and registration, fill out citation, and check for warrants was reasonable in duration); United States v. Briseno, 163 Fed. Appx. 658 (10th Cir. 2006) (a traffic stop of 19 minutes to ask the driver and the passenger about their travel plans, fill out the citation, and check warrants with dispatcher was reasonable in duration); see also Hernandez, 418 F.3d at 1212 n.7 (‘Where at its inception a traffic stop is a valid one for a violation of the law, we doubt that a resultant seizure of no more than 17 minutes can ever be unconstitutional on account of its duration: the detention is too short.”). The 12-minute duration of Morlock’s stop did not violate the Fourth Amendment’s prohibition on unreasonable seizures.
II. Recent United States Supreme Court Cases Strongly Indicate that an Officer May Ask Questions About Travel Plans During a Traffic Stop so Long as It Doesn’t Unduly Extend the Duration of the Stop.
Morlock also complains that the officer shouldn’t have been allowed to ask him about his travel plans. Morlock argues that this *244unnecessarily extended the duration of his traffic stop. But his claims once again seem to run counter to recent decisions of the United States Supreme Court, including Caballes and Muehler.
The Caballes decision by itself has led the authors of the leading treatise on Fourth Amendment law to change their view about both travel-plan questions and drug-dog sniffs. Before Caballes, those authors argued as of 2004 that drug-dog sniffs and questions about travel plans were similarly forbidden during a car stop in which an officer has no reasonable suspicion of drug activities: “[T]he officer may not question the vehicle occupants about drugs, may not quiz them about the details of their past and pending travels, may not seek a consent to search the vehicle for drugs, and may not lead a drug-sniffing dog around the stopped vehicle.” LaFave, Israel & King, Criminal Procedure § 3.8(b) (Hornbook Series, 4th ed. 2004). After the Supreme Court’s 2005 rejection of their position that dog sniffs were illegal absent reasonable suspicion, the chastened authors dropped their claim that an officer could not ask about travel plans. Their book supplement removed the previous text and now notes that Caballes “severely weakened the ‘scope’/ ‘intrusiveness’ limitation by holding that an investigative technique, even when directed toward criminality not reasonably suspected, does not violate that limitation unless the particular tactic employed ‘itself infringed [the detainee’s] constitutionally protected interest in privacy,’ i.e., was itself a search.” LaFave, Israel & King, § 3.8(b) (Hornbook Series, 2007 Supp.).
Most courts that have recently addressed whether questions may be asked about travel plans have focused on Muehler s impact, probably because its facts dealt with police questioning rather than the use of drug dogs. In Muehler, the Court held that law-enforcement officers could ask questions unrelated to the purpose of a search when executing a search warrant in a private residence. Perhaps no place has as much constitutional protection as one’s home, and the person in Muehler was restrained in handcuffs while questioned. Most courts have concluded that the Court’s analysis in Muehler is fully applicable to a person questioned during a police stop of a motor vehicle. See Mendez, 476 F.3d at 1080 (concluding that Muehler s “reasoning is equally applicable in the traffic stop *245context”); United States v. Hernandez, 418 F.3d at 1209 n.3 (concluding that Muehler s “focus on duration [and not scope of questioning] is just as applicable to a lawful traffic stop”); Harris, 228 Ill. 2d at 243 (concluding that the applicability of Muehler to a traffic stop “cannot be questioned”).
Accordingly, an officer may ask questions during a traffic stop that don’t relate to the purpose of tire stop so long as the duration of the stop is not appreciably extended. Courts adopting this view so far and citing Muehler include the United States Courts of Appeal for the Fourth Circuit, Soriano-Jarquin, 492 F.3d at 501; the Eighth Circuit, Olivera-Mendez, 484 F.3d at 510-11; the Ninth Circuit, Mendez, 476 F.3d at 1080-81; and the Tenth Circuit, Stewart, 473 F.3d at 1267, 1269; as well as state appellate courts in Idaho, Stewart, 145 Idaho at 646-47; Illinois, Harris, 228 Ill. 2d at 242-43; Indiana, Pearson, 870 N.E.2d at 1066; Virginia, Briggs, 2006 WL 850667, at *4; and Wyoming, Marinaro, 163 P.3d at 835; see also Martin, 422 F.3d at 600-02 (citing Caballes).
If these courts are right, then officers do not violate the Fourth Amendment by asking questions unrelated to the reason for the stop so long as its duration is not extended. And if that’s the case, then the officer’s brief questions for Morlock and his son present no Fourth Amendment problem; the questions did not appreciably extend the duration of this very brief traffic stop. The portion of the stop during which all of the questions were asked took less than 3 minutes and also included the time for the officer to (1) walk up to the van, (2) approach O’Kelly, (3) have O’Kelly step out of the vehicle, (4) explain the reason for the stop, (5) ask O’Kelly for his ID and the registration, (6) learn the van was a rental, (7) approach Morlock, (8) ask Morlock for the rental agreement, and (9) wait for Morlock to find the rental agreement. These actions are all clearly within the scope of permissible conduct under the Fourth Amendment even under the defendant’s arguments.
III. Even Under Traditional Rules, the Officers Actions with Morlock Were Within the Proper Scope of a Traffic Stop.
Most courts have focused more on Muehler tiran on Caballes when deciding what the limits of police conduct are during a car *246stop. This is perhaps because the use of drug dogs is much less frequent than the use of questions, and Muehler seems to more clearly address how and whether the Fourth Amendment limits questioning. As noted, courts elsewhere have held that Muehler s ruling applies to car stops, so questions may be asked so long as the duration of the stop is not extended.
But the Kansas Supreme Court appears to have read Muehler differently. In State v. Smith, 286 Kan. 402, 419, 184 P.3d 890 (2008), the court said that it was “not persuaded that [Muehler] can be read as an alteration or abandonment of the rules regarding the limited scope of a Terry stop.” One of the rules traditionally applied in Kansas has been that “a detention may not exceed the scope or duration necessary to carry out the purpose of the traffic stop.” (Emphasis added.) State v. Thompson, 284 Kan. 763, 774, 166 P.3d 1015 (2007). The Kansas Supreme Court emphasized that Muehler involved the execution of a warrant that a neutral magistrate approved, Smith, 286 Kan. at 413-14, and that a warrant is not needed for a car stop. The court also emphasized that United States Supreme Court opinions issued shortly before Muehler had not suggested any change in the standard rules for the scope of a Terry stop. 286 Kan. at 414-19.
Before considering more carefully what the Smith opinion’s discussion of Muehler may mean for Morlock’s case, let’s just assume for the moment that it means that the traditional scope rule for Terry stops still applies. Under that test, the detention “may not exceed the scope or duration necessary to carry out the purpose of the traffic stop.” Thompson, 284 Kan. at 774. Would the officer be allowed to ask Morlock for his ID, run a warrant check, and ask limited questions about travel plans? The answer is yes because the Terry scope limitation was never strictly applied.
Because the Fourth Amendment prohibits only unreasonable searches and seizures, the balancing of divergent interests like public safety and the personal interest in being left alone often makes it difficult to establish bright-line rules, and those that exist often have exceptions. And the supposedly bright-line scope test for traffic stops is much the same; that test has never been applied in a purely literal fashion.
*247When a person is stopped for changing lanes without signaling, what would be the scope of the stop if only information directly related to that offense could be checked? The officer could ask whether the person knew he or she hadn’t signaled when changing lanes. The officer could ask for the person’s ID so that the citation could be written out to the right person. But the lane change isn’t relevant to whether the car is registered in the name of the driver, whether the driver has insurance, or whether the car is even registered at all. If the scope limitation for Terry stops were literally applied, all of that would be off limits.
Yet it’s routinely accepted that the officer may ask for vehicle registration and insurance information because the Fourth Amendment balances the public interest in checking for these items against the intrusion to the individual. This balancing act was on display in Delaware v. Prouse, 440 U.S. 648, 59 L. Ed. 2d 660, 99 S. Ct. 1391 (1979), in which the Court ruled that drivers could not be stopped purely at an officer’s discretion to check for a valid driver’s license and vehicle registration. But the Court recognized a state’s need to ensure that only qualified drivers in qualified vehicles are on the roadways as a matter of public safety. 440 U.S. at 658-59. The Court noted that these matters may be checked upon during routine traffic stops when violations have been observed: “Vehicle stops for traffic violations occur countless times each day; and on these occasions, licenses and registration papers are subject to inspection and drivers without them will be ascertained.” 440 U.S. at 659. Because these papers are subject to check in routine traffic checks, the Court found that “[t]he marginal contribution to roadway safety possibly resulting from a system of spot checks” didn’t justify the intrusion when done merely at an officer’s discretion. 440 U.S. at 661.
Similarly, in New York v. Class, 475 U.S. 106, 89 L. Ed. 2d 81, 106 S. Ct. 960 (1986), the Court held that an officer could check the vehicle identification number (VIN) during a traffic stop in part because VINs are used to check for stolen vehicles, which also are more likely to be involved in accidents. 475 U.S. at 111. But VIN’s have nothing to do with the purpose of the typical traffic stop.
*248Thus, despite the logical limits of the scope-of-the-stop test, Kansas courts, like those in other states, have routinely held — -just as Prouse suggests — that license and registration papers are subject to review during a typical traffic stop. State v. Mitchell, 265 Kan. 238, Syl. ¶ 4, 960 P.2d 200 (1998). Kansas also allows the officer to have the driver “produce[] . . . proof that he or she is entitled to operate the car.” 265 Kan. 238, Syl. ¶ 4. Officer safety has nothing to do with a lane-change violation either, but the dangers inherent in traffic stops are quite real. Thus, despite the logical limits of the scope-of-the-stop test, officers are allowed to do several things in the interest of officer safety: check for warrants, Mitchell, 265 Kan. 238, Syl. ¶ 4 (referencing “computer checks”), remove drivers from the vehicle, Pennsylvania v. Mimms, 434 U.S. 106, 54 L. Ed. 2d 331, 98 S. Ct. 330 (1977), and even remove passengers from the vehicle, Maryland v. Wilson, 519 U.S. 408, 137 L. Ed. 2d 41, 117 S. Ct. 882 (1997), all without reasonable suspicion or probable cause to believe they are a danger. All of these activities also extend the duration of the stop, but the delay due to these functions is considered reasonable in light of the interests at stake.
Of course Morlock was not a mere passenger. He was the father of the driver, and he was the only person who claimed an ownership interest in the van. The officer certainly had a right to check the rental agreement, which is equivalent to typical registration papers. The officer could also check Morlock’s ID to confirm that he was the person listed on the rental agreement. When applying the traditional Terry scope test, courts have agreed that an officer may seek registration information from a passenger who is the car’s owner or renter. E.g., State v. Rubio, 136 P.3d 1022 (N.M. App. 2006) (held proper to get ID and run warrant check on passenger who was owner of vehicle); United States v. Hunter, 471 F.2d 6 (9th Cir. 1972) (held proper to ask passenger for ID when driver claimed ownership of car and registration showed he was not); McKoy v. State, 127 Md. App. 89, 101, 732 A.2d 312 (1999) (held proper to ask the passenger for ID when the officer learned the driver was not an authorized driver of the rental car); see also United States v. Garcia, 167 Fed. Appx. 737, 740 (10th Cir. 2006) (an officer properly obtained the rental agreement from passenger/ *249grandfather after stopping his 17-year-old driver/grandson as it was within the scope of the traffic stop to confirm registration and ownership of the vehicle).
The Kansas Supreme Court has recognized that an officer in a traffic stop may check the ID and run a records check of the driver as a matter of routine. In Rubio, the New Mexico court applied caselaw similar to our state’s and noted that the owner-passenger was the person responsible for assuring that the vehicle was properly registered, insured, and for giving permission to the driver to operate the vehicle. The court concluded that the rule allowing ID and records checks of drivers should apply equally to car owners who were passengers: “No different than a minimal detention of an owner-driver for this type of inquiry, the minimal detention of die owner-passenger for these purposes was reasonable and lawful.” 139 N.M. at 617.
But what about asking Morlock and his son about their travel plans and their inconsistent stories? The majority has thoroughly researched the caselaw and presented uniform authorities for the conclusion that an officer may ask about travel plans during a traffic stop. Some cases so holding rely upon Muehler. E.g., United States v. Alcaraz-Arellano, 441 F.3d 1252, 1258 (10th Cir. 2006); United States v. Betancourt, 2008 WL 1970950, at *1 (9th Cir. 2008) (unpublished opinion); Salmeron v. State, 280 Ga. 735, 736, 632 S.E.2d 645 (2006); State v. Ramirez, 2008 WL 2357707, at *3 (Idaho App. 2008) (unpublished opinion); Marinaro v. State, 163 P.3d 833, 835 (Wyo. 2007). But many do not. E.g., United States v. Brigham, 382 F.3d 500, 507-08 (5th Cir. 2004); People v. Williams, 472 Mich. 308, 315-16, 696 N.W.2d 636, cert. denied 546 U.S. 1031 (2005).
In Williams, the Michigan Supreme Court applied traditional Terry stop rules and found that an officer could ask the driver and passengers about travel plans and follow up if their statements were inconsistent. 472 Mich. at 314-16. Similarly, after an exhaustive review of the caselaw, the New Mexico Supreme Court upheld travel-plan questions of the driver and the passenger when that driver had only a handwritten bill of sale and no registration paperwork. State v. Duran, 138 N.M. 414, 424, 120 P.3d 836 (2005). *250The court noted that these questions were asked while the officer was completing steps necessary to process the traffic stop and resulted in a minor delay at most.
In sum, courts have taken two different routes in finding that questioning about travel plans does not violate the Fourth Amendment. Some have relied upon Muehler, concluding that questioning during a detention does not violate the Fourth Amendment unless it unnecessarily extends the duration of the stop. Others have simply held that questions about travel plans are within the scope of a traffic stop. Courts taking both approaches have almost uniformly concluded that officers may ask about travel plans during a traffic stop. But see State v. Gibbons, 248 Ga. App. 859, 547 S.E.2d 679 (2001) (finding that the officer exceeded scope of stop for a seat-belt violation by asking unrelated questions, including ones about travel plans).
If Muehler applies to traffic stops, then questions about travel plans should not present any Fourth Amendment issue unless the traffic stop is unnecessarily extended by those questions. That certainly did not occur here. But even if Muehler does not apply to traffic stops, other courts have concluded that questions about traffic plans are within the scope of the stop after using the traditional test. Without relying upon Muehler, the majority has concluded that the officer could ask the driver and passenger where they were going to and where they were coming from but that he could not ask why they had gone to Phoenix, how long they had been in Phoenix, or why they traveled one way by air and the other by van. But several of the cases cited by the majority approved similar questioning. E.g., Brigham, 382 F.3d at 508 (officers may ask about purpose and itinerary of trip); United States v. Bradford, 423 F.3d 1149, 1153-54, 1156-57 (10th Cir. 2005) (detailed questions about travel itinerary, including questions about the people that the driver said she had visited, held within scope of traffic stop). I would approve similar questioning too so long as it does not unreasonably extend the traffic stop.
IV. The Kansas Case of State v. Damm Does Not Control the Result of Morlock’s Case.
Morlock contends that his rights were violated when tire officer “detain[ed] him without reasonable suspicion of a crime to ask him *251questions unrelated to the stop” and by “detaining [him] for the purpose of running a check of his license.” In support of his claim, he cites State v. Damm, 246 Kan. 220, 787 P.2d 1185 (1990). But that case is not factually similar to Morlock’s. More importantly, the application of this 18-year-old precedent to Morlock’s case would run afoul of several more recent United States Supreme Court decisions interpreting the Fourth Amendment.
First, Damm involved facts quite different from Morlock’s. The defendant in Damm was the driver, not the passenger. The court concluded that running ID checks on all the passengers in the car exceeded the scope of a proper stop of the driver, noting that such a practice could result in a bus driver being detained while the ID’s of all passengers were checked. In addition, the passengers in Damm had no connection to the stop; the driver was stopped for a broken taillight. While the passengers had no ownership or possessoiy interest in the car in Damm, Morlock was the renter of the van and the father of the minor driver. Even when applying traditional car-stop rules about the “scope” of the stop, other courts have allowed an ID check of a passenger who had the ownership interest in the vehicle. E.g., Rubio, 136 P.3d 1022; Hunter, 471 F.2d 6; see also Garcia, 167 Fed. Appx. at 740. The ruling of these courts is consistent with Kansas cases that allow an officer in a traffic stop to check the ID and run a records check of the driver as a routine part of that stop.
Second, the warrant check of a passenger in Damm turned up a warrant; the passenger’s arrest on that warrant led directly to the discovery of drugs in the car and a criminal charge against the driver. Thus, the illegal warrant check on a passenger in Damm resulted in obtaining the critical evidence against the defendant driver. The warrant check on Morlock turned up nothing, had no impact in obtaining evidence against him, and occurred outside his presence.
Third, Damm has been superseded by too many United States Supreme Court precedents that conflict with Damm’s holding. The most significant of these are Caballes and Harris, of course. Harris involved exactly the issue that Morlock presented, and the Supreme Court said to decide that issue “in light of’ Caballes. And *252the Illinois Supreme Court also found that Muehler, an opinion issued only 1 month after the Harris remand order, was significant. But there are others that also undercut the 1990 ruling in Damm:
• Hiibel, 542 U.S. 177 (2004), and Bostick, 501 U.S. 429 (1991), which emphasized that the officer may ask for identification without any Fourth Amendment implication. The Ninth Circuit relied upon Hiibel as a basis for its conclusion that an officer could ask a passenger for ID in Diaz-Castaneda: “The police may ask people who have legitimately been stopped for identification without conducting a Fourth Amendment search or seizure.” United States v. Diaz-Castaneda, 494 F.3d 1146, 1152 (9th Cir. 2007) (citing Hiibel).
• Wilson, 519 U.S. 408 (1997), in which the Court ruled that an officer may routinely ask passengers to exit the vehicle during a traffic stop, just as may be done with the driver. The Fourth Circuit relied upon Wilson as a basis for its conclusion that an officer could ask a passenger for ID in United States v. Soriano-Jarquin, 492 F.3d 495, 500-01 (4th Cir. 2007). The court concluded that surely if you can make the passengers physically leave the vehicle, you can also ask their names: “If an officer may ‘as a matter of course' and in the interest of personal safety order a passenger physically to exit the vehicle, [citation omitted] he may surely take the minimally intrusive step of requesting passenger identification.” 492 F.3d at 500.
Damm is not on point: the defendant there was the driver, but Morlock was the passenger. Morlock had the ownership interest (a rental agreement) in the van; the passengers in Damm had no ownership interest. And the warrant check in Damm led directly to critical evidence, while Morlock’s warrant check led nowhere. Given these factual distinctions and the apparent inconsistency between Damm and six later United States Supreme Court cases, Damm should not be applied here.
V. The Kansas State Case of State v. Smith Does Not Control the Result of Morlock's Case.
After Morlock and the State filed briefs, the Kansas Supreme Court decided State v. Smith, 286 Kan. 402, 184 P.3d 890 (2008). *253Although Smith involves the search of a passenger’s belongings, the holding of the court in Smith is quite narrow. In Smith, officers properly stopped a car in which Smith was a passenger. While the stop was in progress and the parties were not free to drive away, an officer asked Smith for permission to search her purse. Smith consented, and drugs were found. The holding of Smith, then, is drat it is improper to seek a passenger’s consent to search his or her personal belongings during the period of detention of a car stop when that search is not related to the reason for the stop. The Smith opinion did not decide whether an officer may ask a passenger for ID and run a warrant check on the passenger. Nor did it decide what questions may be asked of a passenger.
As I have already noted, the Kansas Supreme Court appears to have read Muehler differendy in Smith than other courts have. But the Smith opinion does not discuss the Harris case or the United States Supreme Court’s direction that whether an officer may run a warrant check on a passenger be decided “in light of’ Caballes. And the discussion of Caballes in Smith was quite limited.
The Smith court did note that the two dissenting justices in Caballes had argued that a dog sniff for drugs was well outside the scope of a traffic stop for speeding. Indeed the dissenting justices did so; they stated their view that the majority had “diminishe[d] the Fourth Amendment’s force by abandoning the second Terry inquiry” of whether an officer’s action was reasonably related to the scope of the stop. Caballes, 543 U.S. at 421 (Ginsburg and Souter, JJ., dissenting). The Smith opinion noted that “[t]he Caballes majority did not disagree with or even discuss this analysis” and speculated that this was because the issue had been narrowly framed by the majority as whether the Fourth Amendment requires reasonable suspicion to use a drug-detection dog to sniff a vehicle during a legitimate traffic stop. 286 Kan. at 414. Of course, a majority opinion decides the case; it need not address every issue or argument mentioned in a dissent. Smith cannot be read to suggest that the comments of two dissenting justices lessen the precedential value of the six-member majority opinion.
Regardless of how the issue in Caballes is framed, the Court determined that the dog sniff did not violate the Fourth Amend*254ment even though the traffic stop for speeding had nothing to do with drugs. And the Court directed that whether a warrant check could be done on a passenger’s ID should be decided “in light of’ Caballes.
Technically, the Smith opinion is not yet a binding precedent because the court has stayed issuance of the mandate. See State v. McGinnis, No. 94,300, unpublished opinion filed September 15, 2006, rev. denied 283 Kan. 933 (2007) (“Until the Supreme Court . . . issues its mandate in the case, Fanning is not binding precedent.”); see also State v. Adams, 280 Kan. 494, 504-05, 124 P.3d 19 (2005) (explaining the citation to an opinion whose mandate had not yet been issued). But Smith’s holding certainly does not control here anyway. Morlock’s detention had ended before the officer asked for consent to search. So unless it. was improper to (1) ask Morloclc for his ID and run the warrant check or (2) ask Morloclc a few questions about his travel plans and that illegality somehow taints Morlock’s consent to search the van, we have a voluntaiy consent during a voluntary encounter. The officer had ended the detention by returning the paperwork, saying, “Have a nice day,” and briefly turning away. A consent search after the detention has ended is fine. See State v. Thompson, 284 Kan. 763, 810-13, 166 P.3d 1015 (2007).
The United States Supreme Court’s decisions in Caballes and Harris are more on point than Smith for deciding Morlock’s case with regard to the warrant check. And the Illinois Supreme Court’s decision in Harris II has faithfully carried out the United States Supreme Court’s directive. On the warrant-check issue, Caballes and Harris must set our path because the Harris case involved exactly the same issue. We must also determine whether limited questioning about travel plans is allowed, including limited but logical follow-up questions. On this issue, Caballes, Harris, and Muehler set our path, and Morlock’s case' follows logically down the path they have set.
VI. Even If the Officer Did Something Improper, the Officer Had Reasonable Suspicion to Justify an Investigatory Detention ofMorlock.
The district court concluded that the entire encounter between Morlock, his son, and the officer was a continuous encounter and *255not voluntary. But the district court determined that it was a proper investigatory detention because the officer had reasonable suspicion of illegal activity.
The district court did not have the benefit of the 2007 decision in Thompson when it determined that this was a continuous encounter, in which Morlock and O’Kelly were detained by the traffic stop and not free to leave throughout. Thompson s facts were nearly identical in that the officer used emergency lights, never drew his weapon, returned the driver’s license, and said, “Have a nice day,” before turning away briefly and then asking if the driver would answer more questions. The Kansas Supreme Court held that a reasonable person would feel free to say no, making it a voluntary encounter at that point if the driver agreed to respond to more questions. See Thompson, 284 Kan. at 810-12.
But if we assume for the purpose of argument that the officer went beyond what’s allowed in a routine traffic stop, then we must review the district court’s determination that the officer had reasonable suspicion of illegal activity so that Morlock and O’Kelly otherwise could be detained for investigation. Reasonable suspicion is something less than probable cause and requires some objective justification; an officer must be able to articulate some specific reason for suspicion, not act merely on a hunch. State v. Moore, 283 Kan. 344, 354, 154 P.3d 1 (2007). Damm recognizes that, based upon reasonable suspicion, a passenger may be held and records checked.
So what made the officer suspicious of Morlock and O’Kelly? The officer discussed several things that might make a person suspicious: (1) O’Kelly’s nervousness; (2) Morlock’s looking straight ahead at the dash at the start of the encounter while the officer talked to O’Kelly; (3) the discrepancy over where the van was rented as the parties said it was from Phoenix but the rental papers showed Tucson, which is 116 miles from Phoenix; (4) the discrepancy over whether the two were visiting Morlock’s girlfriend or a woman Morlock met on the Internet; (5) the discrepancy over whether they saw the woman, with O’Kelly saying they were in Phoenix “visiting his dad’s girlfriend” while Morlock said they “didn’t make contact with” the woman he was going to see; (6) the *256likelihood of taking a one-way flight to Phoenix to visit a woman but then not make contact with her at all; (7) the van was rented; (8) the van was rented for only a one-way trip, which followed a one-way trip by air; (9) the short duration of the trip; (10) more bags in the van than would seem to be needed for a short stay; and (11) the officers previous experience with narcotics arrests on Highway 54.
The district judge correctly noted that “any one of these factors standing alone" would not be enough to justify a detention but that they must be considered together. See Moore, 283 Kan. at 354. Certainly mere nervousness is not enough to give reasonable suspicion, but it may do so when combined with other factors. 283 Kan. at 355.
The officer cited several factors here that are sufficient to provide reasonable suspicion for an investigatory detention. Let’s start with Morlock’s strange behavior in looking straight ahead and avoiding any eye contact either with his son or the officer when that officer approached his 16-year-old son. What dad would rigorously try to avoid eye contact with the officer by only looking forward when his son had been pulled over? We’re not in a contest for worst dad of the year, but that’s quite suspicious. And the officer quickly learned that Morlock was O’Kelly’s dad.
The inconsistencies grew in the story about travel plans as the discussion progressed, and the inconsistencies were significant. O’Kelly said that they “were visiting his dad’s girlfriend” in Phoenix for a couple of days. Morlock said that they had flown one-way to Phoenix from Kansas City “to see a girl he had met on the Internet” but that they had not made contact with her while they were in Phoenix. Morlock said that he didn’t have enough money to buy plane tickets back, so they rented the van. The officer found that suspicious since one-way vehicle rentals are expensive too. Then Morlock produced the rental agreement, and it showed that the van was rented in Tucson, not Phoenix.
The officer didn’t know the exact distance between Phoenix and Tucson, but he knew that they were separate, large cities in Arizona. The existence of reasonable suspicion is an objective test, not a subjective one, Moore, 283 Kan. at 354, so we can check the *257significance of this discrepancy in raising reasonable suspicion by taking judicial notice of the distance between two cities. See Ehrsam v. Borgen, 185 Kan. 776, 778, 347 P.2d 260 (1960). MapQuest shows a distance of 116 miles between Phoenix and Tucson and 118 miles between the cities’ airports. See Saco v. Tug Tucana Corp., 483 F. Supp. 2d 88, 93 n.4 (D. Mass. 2007) (taldng judicial notice of geographical distances based on MapQuest data). The officer testified that he had asked why Morlock flew to Phoenix but rented the van in Tucson. Morlock told him that “he got it at the Phoenix/Tucson Airport.” Morlock claimed, “It’s all right there in one location, and that’s where we rented the vehicle.” But it’s hard to explain how you can rent a van in Tucson when you were visiting Phoenix, given the 116 miles between the two cities. Morlock’s explanation that it was a combined airport serving those two cities only poured gasoline on what was surely an inferno of suspicion.
The district court in an oral ruling found that the officer had reasonable suspicion to detain Morlock and O’Kelly while investigating further, citing several suspicious factors:
“While he’s gathering information, he’s told that the trip originated in Phoenix, and yet the real contract shows Tucson. When the defendant says, it’s the Phoenix/ Tucson Airport, that further arouses his suspicion.
“In talking to Mr. O’Kelly, the driver, the female friend in Phoenix is referred to as girlfriend, while Mr. Morlock, the defendant, refers to her as someone he met on the internet. So that’s an inconsistency that triggers his suspicion.
“In the evidence, the deputy then learned that apparently this person was not even contacted in Phoenix, even though they traveled all the way from Kansas City to Phoenix for that stated purpose.”
The district court also noted the nervousness of the driver, the one-way rental agreement, and the observation of several bags for a 2-day trip as factors supporting reasonable suspicion. The district court’s conclusions are on the mark, but the story is even more suspicious when it is combined with the officer’s testimony about his drug-trafficking training.
The United States Supreme Court has said that an officer’s observations may be supplemented by “consideration of the modes or patterns of operation of certain kinds of lawbreakers.” United *258States v. Cortez, 449 U.S. 411, 418, 66 L. Ed. 2d 621, 101 S. Ct. 690 (1981). The Kansas Supreme Court has also recognized that reasonable suspicion may be based in part upon the training of law-enforcement officers combined with observations that might not seem significant to a layperson without such training. Moore, 283 Kan. at 359-60. The officer testified that the one-way van rental was a highly significant factor based upon his training:
“The tiling about a one-way rental, is that they cost so much to rent a car and drive it one way.
“The other thing is, in all the interdiction classes that I’ve attended, and the KHP, Kansas Highway Patrol officers I’ve spent time with, they’re very proficient at interdiction.
“And compounded with my experience is that, that’s a way to smuggle drugs. You fly down, you go pick up — you rent a car, you pick up the drugs, and you transport it. That’s definitely a warning sign that should go off in your head about interdiction, plus with all the other factors that we had in this case.”
The officer, Deputy Sheriff Henry Cocking, had 15 years of experience, the last 4 as the drug-dog handler. He’d received training in drug interdiction. From that training, from reading reports for law enforcement, and from talking to other officers, he was aware that U.S. 54 leads to some major source areas for drugs in the southwest United States and that there had been quite a few drug seizures from vehicles on that highway. With the officer’s drug-interdiction training and the other facts noted, he had plenty of reasonable suspicion that Morlock was transporting drugs.
To sum up the evidence leading to suspicion, then, we have a father and his 16-year-old son who are returning from Phoenix. The son has missed school to accompany his dad on a trip designed to allow his dad to visit a woman there, but they didn’t make contact with her according to the father. The father and son have different stories about the woman’s relationship with the dad. They flew down on a one-way ticket but didn’t have enough money to buy a return flight, so they rented a van for a one-way return trip. Both father and son only mention visiting Phoenix, but the van was rented in Tucson. The father claims that they rented tire van at the combined Phoenix/Tucson airport. One-way vehicle rentals are quite expensive and often indicate drug-trafficking activity, espe*259daily when the driver has flown to the location from which the vehicle was rented. In addition, two men who had been gone “a couple” of days have four bags, which the officer considered excessive and another sign of possible drug trafficking based on his training.
No reasonable person could consider all of these facts and argue against reasonable suspicion. Reasonable suspicion requires only some articulable, objective basis to believe that some criminal activity “may be afoot.” The basis for suspicion must be objective, but the “level of suspicion is considerably less than proof of wrongdoing by a preponderance of the evidence.” United States v. Sokolow, 490 U.S. 1, 7-10, 104 L. Ed. 2d 1, 109 S. Ct. 1581 (1989). The officer referenced much here that suggested criminal activity may have been afoot.
But the defendant may argue that some of the facts supporting reasonable suspicion were learned through the officer s allegedly illegal conduct. Therefore, we must examine what facts might have been learned through conduct that arguably went beyond permissible limits for a traffic stop. Let’s consider two different scenarios that depend upon which of the officer’s actions the defendant argues is illegal.
First, if we assume that Damm remains good law, it was improper to run a warrant check on Morlock. Even so, it was surely proper to ask him for ID under Hiibel and other cases since he was the person with authority to possess the van under the rental agreement. The officer learned all of the information noted here before he ran the warrant check. Of the factors that the officer cited as suspicious, only the observation of too many bags for a short-duration trip came after the officer had obtained Morlock’s license and the rental agreement. But the officer had all of the suspicious information in his possession before he ran the warrant checks in his patrol car, and he had a right to run a warrant check on O’Kelly and write the ticket in his patrol car anyway. So he was bound to see the bags on the return to his car whether he had Morlock’s license or not. Even if the observation about excessive bags is taken out of the mix, there were sufficient grounds here for reasonable suspicion.
*260Second, if we assume that the officer may ask basic travel plans, but only tightly limited follow-up questions, then the officer would still have learned a great deal of the cited information. But it is truly hard to figure out how an officer could be barred from followup questions when the information received is so inconsistent. As the inconsistencies piled up, the officer appropriately followed up. See People v. Williams, 472 Mich. 308, 316, 696 N.W.2d 636 (finding no violation in asking travel-plan questions of driver and passengers, including follow-up questions) (“Implicit in the authority to ask these questions is the authority to ask follow-up questions when the initial answers given are suspicious.”), cert. denied 546 U.S. 1031 (2005); United States v. Garcia, 167 Fed. Appx. 737, 740 (10th Cir. 2006) (finding no violation in asking passenger for registration papers after determining that driver could not show he was “entitled to operate the vehicle”).
Nonetheless, what did the officer know just from asking destination information of both parties and reviewing the rental agreement? The majority has concluded that the officer .could ask where the parties were going and where they had come from; the majority also concluded that the officer could ask a follow-up question when the rental agreement said Tucson but both Morlock and O’Kelly had mentioned only Phoenix. So, without relying on any potentially “tainted” information, the officer knew that (1) the parties had gone to Phoenix from Kansas (where the licenses showed O’Kelly and Morlock lived); (2) had rented a van in Tucson for a one-way return; (3) had flown to Phoenix one-way; (4) claimed that there was a nonexistent Phoenix/Tucson airport; and (5) had several size-able bags in their van. Between them, Morlock and his son had a large red duffle bag, a medium black suitcase, a large black suitcase, and a medium black nylon bag. When considered along with the officer’s training about drug trafficking, these facts are still sufficient for reasonable suspicion.
We can gauge the significance of the facts in Morlock’s case by comparing them to other cases. In State v. DeMarco, 263 Kan. 727, 952 P.2d 1276 (1998), the district court concluded that the officer did not have sufficient basis for reasonable suspicion. The Kansas Supreme Court affirmed and noted that “the district judge heard *261the witnesses and observed their demeanor” and that the court should not “substitute our view of the evidence for that of the district court.” 263 Kan. at 741. The officer in DeMarco identified eight factors in support of reasonable suspicion: (1) nervousness; (2) departure from Los Angeles, a major source city for narcotics; (3) an unusual travel route; (4) travel in a rental car; (5) travel on a highway commonly used for drug trafficking; (6) a short travel period; (7) inconsistencies in how one party traveled to Los Angeles; and (8) a criminal record. The Kansas Supreme Court called it a close case but found that the inconsistent statements of how one party traveled to Los Angeles were not as marked as inconsistencies in other cases where suppression was denied. The court also discounted the use of a rental car and travel from Los Angeles. 263 Kan. at 740-41.
The inconsistencies in the travel story between O’Kelly and Morlock are far greater than those in DeMarco. Phoenix and Tucson are 116 miles apart; neither O’Kelly nor Morlock mentioned Tucson until the officer saw the rental agreement. Then Morlock said he rented the car at a “Phoenix/Tucson airport,” but each city has its own airport. The inconsistency in DeMarco about travel plans only related to a prior leg of the trip and involved whether one occupant flew or drove to Los Angeles. That inconsistency pales in comparison to the ones here about the location of the trip itself, the purpose of the trip, and the actual events on this trip while in Phoenix. The discrepancy about the nonexistent Phoenix/Tucson airport by itself is far more significant than the discrepancy in DeMarco.
In close cases, our Supreme Court has deferred to the judgment of the district court, which hears the witnesses, and sometimes to the judgment of the officer when that officer has substantial experience that seems relevant. DeMarco, 263 Kan. at 741; Moore, 283 Kan. at 360; State v. Hardyway, 264 Kan. 451, 459-60, 958 P.2d 618 (1998). The officer in Morlock’s case had been involved in narcotics investigations for more than 15 years at the time of Morlock’s arrest. He had been involved in at ieast four major narcotics seizures on Highway 54 in the prior year, and he had specific training in drug trafficking. He said that the bags in the van were *262consistent with the manner in which narcotics are generally transported and that a one-way trip by air followed by a one-way trip by car or van was often a sign of drug trafficking.
We should avoid substituting our view of the evidence for that of the district court when its decision is supported by substantial evidence. DeMarco, 263 Kan. at 741. Ample evidence supports the district court’s conclusion here. In addition, that conclusion is supported by several decisions in similar cases. E.g., Moore, 283 Kan. at 355-60 (reasonable suspicion found on the driver’s nervousness, an odor of fabric softener, a travel route from Las Vegas to Maryland, little clothing in the car, and the car was not registered to the driver; there were no inconsistent statements between individuals because the car had only one occupant); United States v. Powell, 2008 WL 1989665 (10th Cir. 2008) (reasonable suspicion found on a rental car, out-of-place luggage, nervousness, and a smell of deodorizer with no statements of inconsistent travel plans); see also DeMarco, 263 Kan. at 738-39 (discrepancies in travel plans can contribute to reasonable suspicion); United States v. Zubia-Melendez, 263 F.3d 1155, 1162 (10th Cir. 2001) (dubious or inconsistent answers can contribute to reasonable suspicion); United States v. Wood, 106 F.3d 942, 946-47 (10th Cir. 1997) (unusual travel plan or inconsistent information can contribute to reasonable suspicion); United States v. McRae, 81 F.3d 1528, 1535 (10th Cir. 1996) (implausible or contradictoiy travel plans can contribute to reasonable suspicion).
The evidence in Morlock’s case is sufficient for reasonable suspicion based on these cases. But to the extent that others consider it a close question, we should defer in this case to the judgment of the district court, which heard the evidence directly. The officer had reasonable suspicion to justify an investigatory detention of Morlock.
VII. Even if the Officer Did Something Improper That Led to Discovery of the Marijuana, Any Taint from That Impropriety Was Attenuated by Morlock's Consent During a Later, Voluntary Encounter.
Under the exclusionary rule, evidence is generally excluded when it has been directly obtained, or even obtained indirectly *263later, as a result of a government agent’s illegal conduct because that evidence is the “fruit of the poisonous tree,” though this rule is subject to some exceptions. See Nardone v. United States, 308 U.S. 338, 341, 84 L. Ed. 307, 60 S. Ct. 266 (1939).
But what if there is no causal connection at all between the unlawful conduct and the challenged evidence? Logically, there is no fruit of the poisonous tree to exclude from evidence, and that’s largely our case.
Once again, we must separately consider the actions of the officer that Morlock claims were improper. The warrant check did not lead to any fruit, poisonous or otherwise. The warrant check came back negative, and there’s no evidence the officer told Morlock about it. Moreover, that check did not delay Morlock at all— unless we are to assume that Morlock was going to leave his 16-year-old son alone on a highway, with or without the van, while the officer wrote out the son’s ticket and lawfully checked for warrants on the son. Morlock certainly did not present evidence or argue that he was going to leave while the stop of his son was in progress. With no “fruit of the poisonous tree,” there’s no logical basis to exclude any evidence. As the Kansas Supreme Court recently noted, the exclusionary rule bars the admission of evidence obtained “as a result of’ the illegal conduct. State v. Poulton, 286 Kan. 1, Syl. ¶ 2, 179 P.3d 1145 (2008); see also Segura v. United States, 468 U.S. 796, 813-16, 82 L. Ed. 2d 599, 104 S. Ct. 3380 (1984) (holding that the initial illegal entry of the premises did not require the suppression of evidence later obtained in the execution of the search warrant because the warrant affidavit was based only on the information obtained before the illegal entry); Hudspeth v. State, 349 Ark. 315, 321-22, 78 S.W.3d 99 (2002) (“It is well established that only evidence that is discovered by exploitation of an illegality can be suppressed as ‘fruit’ of the poisonous tree.”). Simply, the evidence found in the luggage was not found “as a result” of any illegal police conduct and may not be suppressed based on the warrant check.
So what about the travel-plan questions that Morlock also complains about? In my view, of course, the officer had reasonable suspicion to detain Morlock to investigate possible criminal activity *264based even on the information obtained through questions the majority opinion approves. But let’s assume for purposes of this discussion that the officer didn’t have reasonable suspicion without resorting to the information obtained through questions that the majority finds improper.
What then was the causal connection between those additional questions and Morlock’s consent to search the car? Perhaps they led to the officer asking for consent to search the van. It seems much more likely, though, that this officer trained in drug interdiction would have asked permission for a consent search at the end of the traffic stop based only on the information the majority concedes he obtained with proper questions. If so, then the few extra questions and additional information had no impact on the situation, thus producing no fruit. If there’s doubt about my conclusion that the officer would have asked permission for a consent search of the van without regard to the tainted extra information, the proper course would be to remand to the district court to determine that factual question from the evidence it heard. See Murray v. United States, 487 U.S. 533, 542-44, 101 L. Ed. 2d 472, 108 S. Ct. 2529 (1988) (remanding to determine whether request for search warrant was motivated by illegally obtained information or by other, lawfully obtained information) (plurality opinion).
For argument’s sake, though, let’s assume that the officer decided to seek consent to search the van at least in part based on the information he learned from improper questioning. Now there is “but for” causation: but for the tainted information, the officer wouldn’t have sought consent to search the van, which led to the challenged evidence. But the exclusionary rule is primarily designed to deter police misconduct, so “but for” causation is the start of the analysis, not the end. See Brown v. Illinois, 422 U.S. 590, 608-12, 45 L. Ed. 2d 416, 95 S. Ct. 2254 (1975) (Powell, J., concurring).
The next question is whether an exception to the exclusionary rule applies. The exception at issue in Morlock’s case is attenuation: when the connection between the illegal conduct and the challenged evidence “has become so attenuated as to dissipate the *265taint,” exclusion of the evidence is not required. Nardone, 308 U.S. at 341.
One of the leading cases is Wong Sun v. United States, 371 U.S. 471, 9 L. Ed. 2d 441, 83 S. Ct. 407 (1963), which is still recognized in Kansas as the source of the attenuation rule. Smith, 286 Kan. at 419. In Wong Sun, one man made some statements in his own bedroom after six or seven officers broke down his door and entered. These statements were held inadmissible because his agreement to talk came so quicldy after the unlawful act that it was “unreasonable to infer that [his] response was sufficiently an act of free will to purge the primary taint of the unlawful invasion.” 371 U.S. at 486. But the statement of another defendant who returned to the police station several days later was admissible because any taint from the unlawful conduct had dissipated. 371 U.S. at 491.
The Kansas Supreme Court states that “a court may find that the poisonous taint of an unlawful search or seizure has dissipated because the connection between the unlawful law enforcement conduct and the challenged evidence became attenuated.” State v. Martin, 285 Kan. 994, Syl. ¶ 3, 179 P.3d 457 (2008). We examine “the causal chain between unlawful conduct and the acquisition of evidence.” 285 Kan. 994, Syl. ¶ 4. Three factors are commonly used to judge attenuation: (1) the time elapsed between the illegal conduct and acquisition of the evidence; (2) the presence of intervening circumstances; and (3) the “purpose and flagrancy” of the official misconduct. Martin, 285 Kan. at 1003 (citing Brown, 422 U.S. at 603-04 [1975]).
The first factor is in the defendant’s favor. Very little time elapsed between tire travel-plan questions and Morlock’s consent to search the van.
The second factor is in the State’s favor. There was an intervening circumstance: the encounter had changed from a Terry stop, in which Morlock and O’Kelly were not free to leave, to a voluntary encounter in which they were free to go on about their business. The officer’s routine in this case was virtually identical to the actions found in Thompson that indicated the traffic stop had ended, the driver was free to go, and a voluntary encounter had begun. Many other courts have concluded that telling a driver that he’s *266free to go is an intervening circumstance for purposes of analyzing attenuation in a traffic stop. E.g., United States v. Esquivel, 507 F.3d 1154, 1160 (8th Cir. 2007); United States v. Infante-Pineda, 2002 WL 32657208, at *8 (D. Neb. 2002) (unpublished opinion), aff'd 366 F.3d 961 (8th Cir. 2004); State v. Harkless, 1995 WL 756571, at *7 (Ohio App. 1995) (unpublished opinion); State v. Garcia, 123 S.W.3d 335, 347 (Tenn. 2003), cert. denied 541 U.S. 974 (2004); cf. United States v. Santiago, 310 F.3d 336, 343 (5th Cir. 2002) (finding no attenuation because the officer had not yet returned paperwork when the consent to search was sought and, thus, there was no intervening circumstance since the defendant was not yet free to leave). But see People v. Rodriguez, 945 P.2d 1351, 1364-65 (Colo. 1997) (no intervening circumstance when officer said driver was free to go and asked permission to search literally “[w]ith the same breath”).
The third factor is also in the State’s favor. As to flagrancy of the illegal conduct, there is none. The exclusionary rule recognizes that flagrant conduct — like six or seven officers unlawfully breaking down a bedroom door — is likely to have repercussions that a technical violation would not. Nor is there reason to believe that the officer intentionally did anything unlawful.
If this opinion demonstrates anything, I hope that it demonstrates that there is a reasonable basis for a police officer to believe that a few questions about travel plans and a warrant check may lawfully be done with a passenger in a traffic stop. That basis is even greater in Morlock’s case since he had the ownership interest in the rented van. Any illegality here was minor and technical and wholly unknown to Morlock when he gave his consent.
When considering these factors, no single factor is determinative, though many courts consider the third factor the most important because it is directly tied to tire goal of the exclusionary rule, which is deterring police misconduct. State v. Lane, 726 N.W.2d 371, 388 (Iowa 2007) (plurality opinion). The goal is to prevent “exploitation of [the] illegality” by police. Wong Sun, 371 U.S. at 488. Therefore, when considering consent for a search that’s given after some illegal police conduct, the real question is whether the consent is the product of that illegality or whether it *267has come “ ‘by means sufficiently distinguishable to be purged of the primary taint.’ ” Lane, 726 N.W.2d at 382 (quoting Wong Sun, 371 U.S. at 488).
The officer’s request to search Morlock’s van came after the officer had returned all paperwork to Morlock and his son and essentially told them they were free to leave. All of the brief conversation the officer had with Morlock and O’Kelly was in a conversational tone. There’s not a hint of coercion here and no reason to believe that Morlock agreed to the search because he felt he had to since he had been asked a few questions about his travel plans. And even though the intervening circumstance in Morlock’s case is not as strong as the voluntaiy trip to the police station several days later in Wong Sun, there is little if any causal connection between the supposed illegal conduct and Morlock’s consent.
The United States Court of Appeals for the Eighth Circuit found attenuation and upheld a consent search in Esquivel, a somewhat similar case. The officer in Esquivel stopped three men who were driving in a rental car with no license plate. The officer didn’t see a temporary registration permit or in-transit sticker, although he was able to confirm shortly after stopping the vehicle that it had a valid temporary permit. The officer asked the driver questions about travel plans and other matters but didn’t proceed to write the warning ticket and let the driver go when he received radio confirmation that there were no warrants for the driver. Instead, he kept the driver in his patrol car while he went to question the two passengers about their travel plans, took their ID’s, and ran a warrant check on them. Nearly 10 minutes passed before he finally gave the driver his warning citation and told the group they were “done with the traffic stop” and to have a safe trip. The officer followed that up with a request to ask more questions and then a request to search the van, just as occurred in Morlock’s case.
The Eighth Circuit assumed for its decision that the officer had gone beyond what was permitted in the traffic stop but found that the consent to search the vehicle was voluntary and that the consent was free of any taint from any illegality. The court applied the same factors from Brown that are applied in Kansas. Despite the temporal proximity, the court emphasized that “the Trooper’s an*268nouncement that the traffic stop was over and [the defendant] was free to leave was ... an intervening circumstance between the presumed illegal detention and the consent.” The court also noted that no intentional misconduct had been found by the district court. 507 F.3d at 1160; see also United States v. Johnson, 2006 WL 435975 (W.D.N.C. 2006) (unpublished opinion) (finding consent free of taint when defendant knew he was free to go and officer s error in opening car door to look at VIN was minor, only “minimally intrusive,” and not purposeful), aff'd 258 Fed. Appx. 510 (4th Cir. 2007). I would therefore find that any taint of illegal conduct was attenuated in Morlock's case.
Conclusion
The Fourth Amendment contains 54 words. If their meaning were not subject to debate, many trees would have been saved, many disputes averted, and Professor Wayne LaFave would not have been able to publish a multi-volume treatise containing by his count 1,687,149 words, mostly on the interpretation and application of the Fourth Amendment.
The Fourth Amendment prohibits only unreasonable searches and seizures, and what’s reasonable is largely subjective. For guidance, we must rely upon — and ultimately abide by — the rulings of the United States Supreme Court. Its rulings as they relate to Morlock’s warrant check are quite clear, which the Illinois Supreme Court unanimously determined in Harris II. The check of Morlock’s name for outstanding arrest warrants did not appreciably lengthen this lawful traffic stop. And checking a passenger’s name for warrants is even less intrusive than having a drug dog walk around the perimeter of a car, which the Court found proper in Caballes. Moreover, asking a few questions about travel plans is consistent with several Supreme Court rulings and caselaw elsewhere. Nothing in the Fourth Amendment was violated. No evidence should be suppressed.
I would affirm the district court’s judgment.