Opinion for the Court filed by Circuit Judge SILBERMAN.
In this appeal, appellant challenges the district court’s denial of his motion to suppress statements and evidence that stem from his encounter with detectives aboard an Amtrak train during its short stopover at Union Station, Washington, D.C. We think the district court’s ruling was proper and therefore affirm the conviction.
I.
On April 27, 1988, Amtrak representatives in Washington, D.C. provided Detective John A. Centrella, a member of the Narcotics Squad of the District of Columbia Metropolitan Police Department assigned to the Amtrak Drug Interdiction Unit at Union Station, with the following information regarding a passenger who would be traveling through Union Station on Amtrak that day: The passenger (1) under the name, “Bob Jones”; (2) purchased a round-trip ticket on the same day on which he had made his reservation; (3) from West Palm Beach, Florida to Baltimore, Maryland and back; (4) reserving a sleeper car (roomette) for the trip to Baltimore, but only a coach seat for the return trip to West Palm Beach; (5) used cash; (6) and provided Amtrak with only a pay telephone number for confirmation.
Detective Centrella associated these circumstances with those under which drug couriers are likely to travel. According to Centrella’s testimony in the district court, many drug couriers prefer to travel under simple, common aliases. Florida is known to law enforcement authorities to be a source area for cocaine distributed along the East Coast. Drug couriers are likely to desire privacy while transporting drugs but are indifferent to it after having delivered them. And, travelers offering pay telephone numbers for confirmation are likely not to have a residence in the state from *1115 which they are calling or want to ensure that the location of their residence cannot be verified.
According to Centrella’s account, which the district court credited, Centrella decided to board “Jones’s” train, accompanied by Amtrak Investigator Calvin Burns, to interview him during the train’s twenty minute stopover at Union Station. Centrel-la and Burns knocked on the door of the sleeper car reserved for “Bob Jones” and the occupant of the car answered, “yes?” One of the officers replied, “Amtrak,” and “Jones” slid open the roomette’s door. Centrella then identified himself as a police officer and asked if he could talk with “Jones,” to which “Jones” replied, “sure.” Centrella asked appellant his name and residence, and “Jones” stated that he was “Bob Jones” of Baltimore. In response to Centrella’s question whether he had any identification, “Jones” patted his chest, looked overhead to his suitcase, and replied that he did not. When Centrella then asked him where and for how long he had stayed in Florida and whether he had a train ticket, “Jones” produced and handed to Centrella a ticket with the name “Bob Jones” on it. 1
Centrella chatted with “Jones,” explaining that he was a member of the drug interdiction team in Washington, that the District was experiencing problems with drugs, and that Florida is a source of the majority of the cocaine coming to the East Coast. He then asked “Jones” for permission to look in a small brown suitcase in the sleeper car’s overhead rack which “Jones” had identified as his own. “Jones” replied, “sure,” brought down the suitcase, and handed it to Centrella, who was standing in the train’s aisle. 2 Centrella handed the bag to Burns, who began to search it in the aisle.
While Centrella continued talking with “Jones,” Burns handed him two pieces of identification from the suitcase bearing the name “Thomas Savage.” The district court found that, at this point, Centrella’s questioning became “direct and probably forceful.” Centrella asked “Jones” who “Savage” was, and “Jones” answered, “It’s me.” When Savage was then asked why he was using an assumed name, Savage did not answer, his voice began to crack, and he became uncomfortable. Centrella then pointed to a white cardboard box on the sleeper car’s overhead rack and asked Savage about it. Savage answered that it was a gift of crystal for his mother. Centrella asked if he could look at it. Savage replied, “well ...,” then brought down the box and placed it on the floor in front of Centrella. Centrella again asked Savage if he could look in the box, and Savage again replied, “well.... ” Centrella then reiterated to Savage the question why he was not traveling under his proper name, and Savage again gave no response. Instead, he stated, “You got me. It’s in there.” Centrella asked, “What’s in there?” and Savage answered, “the cocaine.” Centrella asked “How much cocaine?” and Savage responded, “three kilos.” Centrella then arrested Savage, searched the box, found in it three kilograms of cocaine, and escorted Savage off the train. The entire exchange lasted between five and ten minutes.
Following his indictment for possession with intent to distribute more than 500 grams of a cocaine mixture, 21 U.S.C. §§ 841(a) and 841(b)(l)(B)(ii)(II), Savage moved to suppress the statements made and evidence seized during the encounter on the ground that they were obtained in violation of his fourth amendment rights. The district court at a hearing on the motion ruled from the bench that the evidence was admissible. Savage subsequently pled guilty to the charge in the indictment while reserving his right to appeal the district court’s denial of his motion to suppress.
II.
Appellant contends that his encounter with Detectives Centrella and Burns was
*1116
an investigative “stop,” from the outset, unsupported by articulable facts reasonably warranting the intrusion.
See Terry v. Ohio,
Police “seize” a person within the meaning of the fourth amendment “ ‘only if, in view of all of the circumstances surrounding the incident, a reasonable person would have believed that he was not free to leave.’ ”
Michigan v. Chesternut,
In distinguishing between consensual encounters with law enforcement officials that need not be supported by articulable suspicion and those that intrude upon constitutionally protected interests and must therefore be shown to be reasonable, we consider factors bearing on the extent to which the encounters are objectively intimidating.
See, e.g., Michigan v. Chesternut,
To be sure, it is the totality of the circumstances of each case to which we look in determining whether a fourth amendment seizure has occurred.
See id.
at 1979. It is nevertheless instructive to note instances of
particular
police behavior that do not, by themselves, constitute seizures; for those examples of behavior must be altered in some constitutionally meaningful way if they are to be accorded fourth amendment significance. For example, a request by the police for identification does not, by itself, constitute a fourth amendment seizure.
See INS v. Delgado,
Accordingly, when Centrella and Burns asked Savage if he had any identification, and when he could produce none and they asked to see his train ticket, the detectives did not effect a seizure. Centrella then told Savage that he was a member of Washington’s drug interdiction team. But he did not, as in
Florida v. Royer,
With regard to the setting of the encounter, we have found “no merit in [the] ... suggestion[ ] ... that the narrowness and confinement of a train compartment are inherently isolationist, hence coercive.”
United States v. Brady,
When Detective Centrella asked Savage if he might search his suitcase, the encounter was still consensual. The detective requested Savage’s permission to see the bag, and appellant was free to refuse. Indeed, the district court found that Savage, “having nothing, he thought, to conceal with respect to the bag and under the circumstances wishing to allay any suspicions that these agents might have had was probably very compliant in turning the bag over.” See also supra note 2. We do not believe, therefore, that Savage’s encounter with Detectives Centrella and Burns, up to this point, implicated the fourth amendment. 3 Insofar as Savage felt any restraint in his dealings with Detectives Centrella and Burns at this stage, it was due to his apprehension that refusal to cooperate would bring suspicion upon himself. But that concern — which an innocent man would not share — is not a factor that bears on fourth amendment analysis.
The district court concluded, and we agree, however, that Savage’s encounter with the detectives became an investigative “stop,” requiring the support of articulable facts for justification, once Detective Burns discovered Savage’s true identity.
See Terry v. Ohio,
The level of suspicion required to justify a detention short of an arrest is lower than the probable cause required for a valid arrest.
See United States v. Brignoni-Ponce,
We believe that Savage’s initial encounter with officers Centrella and Burns was consensual, that when the encounter escalated to an investigative stop, it was supported by reasonable cause, and that the officers’ search of Savage’s cardboard box was lawful incident to his arrest. We therefore affirm the conviction.
Notes
. The record is silent on when or whether Cen-trella returned the ticket.
. Appellant testified that before the officer requested from him permission to search the suitcase, he “flipped the bag open, trying, you know, to show them there was nothing there that I was trying to hide from them.”
. Even were the district court to have found that the detectives never returned Savage’s train ticket to him,
see supra
note 1, we would still view this portion of the encounter to be consensual. While failing to return a traveler’s ticket after sufficient time to peruse it has elapsed and as his train is about to depart without him may well be tantamount to a detention,
see Florida v. Royer,
. The district court erroneously determined that the search of the box was proper because the police had probable cause to believe it contained cocaine.
See United States v. Place,
