dissenting.
Justice Powell, concurring in United States v. Mendenhall, 446 U. S. 544 (1980), observed:
“The public has a compelling interest in detecting those who would traffic in deadly drugs for personal profit. Few problems affecting the health and welfare of our population, particularly our young, cause greater concern than the escalating use of controlled substances. Much of the drug traffic is highly organized and conducted by sophisticated criminal syndicates. The profits are enormous. And many drugs . . . may be easily concealed. As a result, the obstacles to detection of illegal conduct may be unmatched in any other area of law enforcement.” Id., at 561-562.
In my view, the police conduct in this case was minimally intrusive. Given the strength of society’s interest in overcoming the extraordinary obstacles to the detection of drug traffickers, such conduct should not be subjected to a requirement of probable cause. Because the Court holds otherwise, I dissent.
The Florida District Court of Appeal, Third District, held that respondent Royer had been arrested without probable cause before he consented to the search of his luggage, and that his consent was therefore tainted by this illegal deten*514tion. I concur in the plurality’s adoption of the Fourth Amendment “seizure” standard proposed by Justice Stewart in Mendenhall: Fourth Amendment protections apply when “official authority” is exercised “such that ‘a reasonable person would have believed he was not free to leave.’ ” Ante, at 502, quoting 446 U. S., at 554. I do not quarrel with the plurality’s conclusion that at some point in this encounter, that threshold was passed. I also agree that the information available prior to the opening of Royer’s suitcases did not constitute probable cause to arrest; thus, if probable cause was required, the seizure was illegal and the resulting consent to search was invalid. Dunaway v. New York, 442 U. S. 200, 216-219 (1979); Brown v. Illinois, 422 U. S. 590, 601-604 (1975). The dispositive issue, however, is whether the officers needed probable cause to arrest before they could take the actions that led to Royer’s consent and the subsequent discovery of the contraband. I conclude that they did not.
A
“ ‘[T]he key principle of the Fourth Amendment is reasonableness — the balancing of competing interests.’ ” Michigan v. Summers, 452 U. S. 692, 700, n. 12 (1981), quoting Dunaway v. New York, 442 U. S., at 219 (White, J., concurring). Previous cases suggest a two-step analysis to distinguish seizures requiring probable cause from those requiring reasonable suspicion. On the one hand, any formal arrest, and any seizure “having the essential attributes of a formal arrest, is unreasonable unless it is supported by probable cause.” Michigan v. Summers, 452 U. S., at 700. On the other hand, a more limited intrusion, if supported by a special law enforcement need for greater flexibility, may be justifiable under the lesser “reasonable suspicion” standard. These lesser seizures are “not confined to the momentary, on-the-street detention accompanied by a frisk for weapons.” Ibid. In the case of a seizure less intrusive than a formal arrest, determining whether the less demanding reasonable-*515suspicion standard will be applied requires balancing the amount of intrusion upon individual privacy against the special law enforcement interests that would be served by permitting such an intrusion on less than probable cause. See Michigan v. Summers, 452 U. S., at 699-701; United States v. Mendenhall, 446 U. S., at 561 (Powell, J., concurring in part); Dunaway v. New York, 442 U. S., at 219-220 (White, J., concurring); United States v. Martinez-Fuerte, 428 U. S. 543, 555 (1976); United States v. Brignoni-Ponce, 422 U. S. 873, 878-881 (1975).
B
At the suppression hearing in this case, Royer agreed that he was not formally arrested until after his suitcases were opened. App. 84A, 85A. In my view, it cannot fairly be said that, prior to the formal arrest, the functional equivalent of an arrest had taken place. The encounter had far more in common with automobile stops justifiable on reasonable suspicion, see United States v. Brignoni-Ponce, 422 U. S., at 880-882, than with the detention deemed the functional equivalent of a formal arrest in Dunaway v. New York, supra. In Dunaway, the suspect was taken from his neighbor’s home and involuntarily transported to the police station in a squad car. At the precinct house, he was placed in an interrogation room and subjected to extended custodial interrogation. 442 U. S., at 203, 206-207, 212. Here, Royer was not taken from a private residence, where reasonable expectations of privacy perhaps are at their greatest. Instead, he was approached in a major international airport where, due in part to extensive antihijacking surveillance and equipment, reasonable privacy expectations are of significantly lesser magnitude, certainly no greater than the reasonable privacy expectations of travelers in automobiles. See United States v. Martinez-Fuerte, 428 U. S., at 561. As in the automobile stop cases, and indeed as in every case in which the Court has upheld seizures upon reasonable suspicion, Royer was questioned where he was found, and all *516questions were directly related to the purpose of the stop. Thus, the officers asked about Royer’s identity, the purposes of his travel, and the suspicious circumstances they had noted. As the plurality appears to concede, ante, at 502, probable cause was certainly not required at this point, and the officers’ conduct was fully supported by reasonable suspicion.
What followed was within the scope of the lesser intrusions approved on less than probable cause in our prior cases, and was far removed from the circumstances of Dunaway. In the context of automobile stops, the Court has held that an officer “may question the driver and passengers about their citizenship and immigration status, and he may ask them to explain suspicious circumstances, but any further detention or search must be based on consent or probable cause.” United States v. Brignoni-Ponce, 422 U. S., at 881-882, quoted with approval in Dunaway, 442 U. S., at 212. Here, Royer was not subjected to custodial interrogation, for which probable cause is required. Dunaway, 442 U. S., at 216. Instead, the officers first sought Royer’s consent to move the detention 40 feet to the police room, and then sought his consent to search his luggage. The question is whether, as in Dunaway, the move was involuntary, in which case probable cause might have been required, or whether, as in Mendenhall, 446 U. S., at 557-558, Royer consented voluntarily to this change of locale. Like Justice Rehnquist, post, at 530-531, I do not understand the plurality to dispute that Royer consented to go to the police room. Because the detention up to this point was not unlawful, the voluntariness of Royer’s consent is to be judged on the totality of the circumstances. Schneckloth v. Bustamonte, 412 U. S. 218, 227 (1973). As in Mendenhall, 446 U. S., at 557, quoting Sibron v. New York, 392 U. S. 40, 63 (1968), Royer went “‘voluntarily in a spirit of apparent cooperation.’”1
*517Had Royer initially refused to consent to the search of his suitcases, and had the officers continued the detention in the hope that he would change his mind, a situation much closer to Dunaway would have been presented. But once he was in the room,2 Royer consented to the search immediately upon request. Neither the plurality nor the Florida Court of Appeal suggests that, judged on the totality of the circumstances, Royer’s consent to the search was involuntary.
*518Thus, the officers in this case followed the formula for “lesser intrusions” set forth in Brignoni-Ponce and approved in Dunaway: beyond the initial stop and properly limited questioning, further detention and search were based on Royer’s consent. Certainly, the intrusion on Royer’s privacy was not so extreme as to make the countervailing public interest in greater flexibility irrelevant to the question whether probable cause was required. Consequently, I do not understand why the plurality fails to balance the character of the detention and the degree to which it intruded upon Royer’s privacy against its justification as measured by “both the law enforcement interest and the nature of the ‘articula-ble facts’ supporting the detention.” Michigan v. Summers, 452 U. S., at 702. This balance should determine whether probable cause or reasonable suspicion was required to support the officers’ conduct, and whether that conduct was lawful under the appropriate standard.
I — I HH
The officers in this case began their encounter with Royer with reasonable suspicion. They continued their questioning and requested further cooperation only as more facts, heightening their suspicion, came to their attention. Certainly, as any such detention continues or escalates, a greater degree of reasonable suspicion is necessary to sustain it, and at some point probable cause will be required. But here, the intrusion was short-lived and minimal. Only 15 minutes transpired from the initial approach to the opening of the suitcases. The officers were polite, and sought and immediately obtained Royer’s consent at each significant step of the process.3 Royer knew that if the search of the suitcases did not *519turn up contraband, he would be free to go on his way.4 Thus, it seems clear to me that “ ‘the police [were] diligently pursuing a means of investigation which [was] likely to resolve the matter one way or another very soon . . . Michigan v. Summers, 452 U. S., at 701, n. 14, quoting 3 W. LaFave, Search and Seizure §9.2, p. 40 (1978).5
The special need for flexibility in uncovering illicit drug couriers is hardly debatable. Surely the problem is as serious, and as intractable, as the problem of illegal immigration discussed in United States v. Brignoni-Ponce, 422 U. S., at 878-879, and in United States v. Martinez-Fuerte, 428 U. S., at 552. In light of the extraordinary and well-documented difficulty of identifying drug couriers, the minimal intrusion in this case, based on particularized suspicion, was eminently reasonable.
I dissent.
The trial judge, App. 115A-116A, and the appellate panel, 389 So. 2d 1007, 1008-1010 (Fla. App. 1979), so found, and the Florida District Court *517of Appeal, which viewed the evidence in the light most favorable to the State, id., at 1016, did not contradict this finding. This is not inconsistent with a possible finding that at the time the request was made, Royer reasonably believed that he was not free to leave the officers’ presence. As the officers framed the request, Royer might have believed that his only choices, for the moment, were to accompany the officers to the police room or to continue the discussion in the public concourse. His consent to moving the discussion, therefore, was voluntary, even if the detention itself was not.
The character of the police room did not transform the encounter into the functional equivalent of an arrest. See post, at 532, and n. 10 (Rehnquist, J., dissenting). Indeed, the plurality does not rely on any differences between this room and the one in Mendenhall to distinguish this encounter from the encounter held in Mendenhall to require at most reasonable suspicion. Ante, at 503-504, n. 9. The plurality instead points to several other differences between this case and Mendenhall: the officers retained Royer’s ticket and identification, momentarily took possession of Royer’s luggage, and did not advise him that he could decline to be searched. Ante, at 504, n. 9. Like Justice Powell, I considered the question whether a threshold seizure had taken place in Mendenhall to be “extremely close.” 446 U. S., at 560, n. 1 (Powell, J., concurring in part). Thus, notwithstanding the facts that, unlike the suspect in Men-denhall, Royer was a well-educated, adult, Caucasian male, cf. id., at 558 (“that the respondent, a female and a Negro, may have felt unusually threatened by the officers, who were white males,” is “not irrelevant” to the degree of coercion), the differences noted by the plurality lead me to agree that a reasonable person in Royer’s circumstances would not have felt free to walk away. But while these differences did transform this otherwise identical encounter from an arguably consensual one into a seizure clearly requiring some justification under the Fourth Amendment, they are not so significant as to require the conclusion that Royer had been subjected to the equivalent of a full-blown arrest.
The officers acted reasonably in taking Royer’s baggage stubs and bringing his luggage to the police room without his consent. Royer had already surrendered the suitcases to a third party, the airline. The officers brought the suitcases to him immediately, and their contents were not revealed until Royer gave his consent. Thus, Royer’s privacy was not substantially invaded. At that time, moreover, Royer himself was validly *519detained, the object of the encounter had become the securing of Royer’s consent to search his luggage, and the luggage would otherwise have been loaded onto the airplane.
The fact that Royer knew the search was likely to turn up contraband is of course irrelevant; the potential intrusiveness of the officers’ conduct must be judged from the viewpoint of an innocent person in Royer’s position. See United States v. Wylie, 186 U. S. App. D. C. 231, 237, 569 F. 2d 62, 68 (1977), cert. denied, 435 U. S. 944 (1978).
Like Justice Rehnquist, post, at 528, I cannot accept the “least intrusive” alternative analysis the plurality would impose on the law of the Fourth Amendment. See ante, at 500. Prior cases do establish that “an investigative detention must be temporary and last no longer than is necessary to effectuate the purpose of the stop.” Ibid. The detention at issue fully met that standard. The cases relied upon by the plurality do not, however, support the further proposition for which it cites them.