(dissenting). I strongly disagree with that por*211tian of the majority opinion that concludes, as matter of law, that the defendant was not subjected to an illegal detention. At issue here is whether police officers, after concluding a routine traffic and investigatory stop, may prolong the motorist’s detention to employ drug-sniffing canines without the requisite reasonable suspicion of narcotics trafficking. Put another way, the question is “whether [the officer’s action] was reasonably related in scope to the circumstances which justified the interference in the first place.” Terry v. Ohio, 392 U.S. 1, 19-20 (1968). is undisputed that the traffic stop was properly initiated in this case. Thus, we need only examine the second part of the Terry test concerning the reasonableness of the officer’s conduct. The Commonwealth has the burden of establishing that the conduct remained within the scope of the stop. Florida v. Royer, 460 U.S. 491, 500 (1983); Commonwealth v. Borges, 395 Mass. 788, 794 (1985).
Here, the Commonwealth has not offered any, let alone sufficient, justification for detaining the defendant to implement a canine sniff. The arresting officer purposely summoned Devlin, a canine officer, who was not present at the time of the stop, to broaden the scope of the traffic stop into a drug investigation without any specific and articulable facts to support the use of a canine sniff. As the majority readily admits, the arresting officer did not arrest the defendant for nonpossession of a license, choosing instead to hold him at the scene while he summoned the dog.
There are no Massachusetts appellate decisions on this point. Opinions from other jurisdictions approaching the issue are not numerous, but they are in harmony. In People v. Cox, the Illinois Supreme Court showed awareness that although stopping the defendant for not having a rear registration light was lawful, the subsequent dog sniff was impermissible, lacking any reasonable and articulable suspicion that the defendant’s vehicle contained a controlled substance. People v. Cox, 202 Ill. 2d 462, 470-471 (2002), cert. denied, 539 U.S. 937 (2003). The court held that a fifteen-minute detention after the stop was not justified in that “[a]n officer may not stall at the scene of a traffic stop until a drug-sniffing dog arrives and creates probable cause to conduct a search of a vehicle.” Id. at 470, quoting *212from People v. Luna, 322 Ill. App. 3d 855, 859 (2001). See People v. Caballes, 207 Ill. 2d 504, 509-510 (2003), cert. granted, 541 U.S. 972 (2004) (in circumstances strikingly similar to the instant case, the same Illinois court held that there was no justification for detaining a defendant stopped for a traffic violation until a canine sniff could be effectuated).
In a recent Federal traffic stop case, United States v. Perkins, the court overlooked the defendant’s “nervousness,” his “odd behavior” of repeating questions asked by the officer, and his possession of a Florida driver’s license while claiming to live in Alabama. United States v. Perkins, 348 F.3d 965, 970-971 (11th Cir. 2003). In the absence of any evidence linking the defendant to drug-related activities, the Perkins court held that police officers lacked authority to call a canine officer to search the car. Ibid.
Here, the defendant did not have a driver’s license in his possession. Thus, it was appropriate for Pinkes to make some inquiries of the defendant and the passenger. See Commonwealth v. Rivera, 33 Mass. App. Ct. 311, 314 (1992); Commonwealth v. Alvarez, 44 Mass. App. Ct. 531, 534 (1998). However, once that task was concluded, the constitutional limitation applicable to a seizure of his person was triggered. “[Tjhere comes a time after a temporary detention when the officer must either arrest the stopped individual or allow him to go free. . . . [E]yen though the investigation has proved inconclusive, the officer must then disengage the individual from official confrontation.” People v. Williams, 63 Mich. App. 398, 404 (1975).
The chain of logic has to be as follows. Once Pinkes determined that the defendant was an unlicensed operator, he had two choices: either arrest him and tow the vehicle for safekeeping or issue him a citation for the offense and permit his passenger, if licensed, to drive both of them to their destination.1 Pinkes chose neither of these routes, but rather a canine investigation, a route that was not proportional to the reasonable suspicion generated by the evidence on the record.
By contrast, Commonwealth v. Sinforoso is a good example *213of an instance where an officer’s conduct was proportional to the escalating suspicion provoked by specific, articulable facts. Commonwealth v. Sinforoso, 434 Mass. 320, 323-324 (2001). During the initial request for license and registration after a properly-initiated traffic stop, the officer noticed weapons on the floor of both the driver’s side and the passenger’s side of the vehicle. Id. at 321-322. At this point, he called for back-up. Id. at 322. Out of concern for his own safety, he, and the other police officer who had arrived, ordered the driver and passenger out of the car and conducted patfrisks. Ibid.
When one of the officers returned to the vehicle to retrieve the weapons, he noticed a nonstandard switch under the dashboard. Ibid. Because of his training and experience, he suspected that the car might have a secret compartment, so he examined the exterior of the car and noticed that the location of the gas tank had been modified to accommodate such a compartment. Ibid. Only then did the officer call for the canine unit to check the car. Id. at 324.
In the instant case there were a few steps missing between finding reason to question the defendant further with regard to his identity, and determining that there were sufficient articulable facts to arouse reasonable suspicion of narcotics trafficking which would justify detaining the driver and passenger to call in and conduct a canine narcotics search. See United States v. Perkins, 348 F.3d at 970; People v. Caballes, 207 Ill. 2d at 509-510.
Pinkes called for the canine unit roughly five minutes after stopping the car. He did not call because he felt unsafe; if that were the case, he would have either pat frisked the defendant after asking him to exit the car or kept the defendant in the car until back-up arrived. See Commonwealth v. Torres, 433 Mass. 669, 675 (2001). Pinkes also did not see anything unusual about the car to suggest the existence of a secret compartment or a “popped out” trunk lock. See Commonwealth v. Sinforoso, supra at 324; Commonwealth v. Valentine, 18 Mass. App. Ct. 965, 966 (1984) (finding “popped out” trunk lock and absence of rear lights adequate stimulus for additional investigation of car once stopped). The information Pinkes had, i.e., that the headlight was out, that the driver could not produce a license, *214that the driver lied about his identity, and that the driver and passenger gave inconsistent answers, supports further questioning with regard to the defendant’s identity, but does not support an immediate inference of possible narcotics trafficking.
From the evidence on the record, it would have been more logical to infer, for example, that the car might have been stolen. See Commonwealth v. Kimball, 37 Mass. App. Ct. 604, 605-606 (1994). The car was registered to another owner, and the driver did not possess his license. Given that both driving without a license and stealing a car are illegal, such a situation might well prompt nervousness and dishonest responses from those in the car. Furthermore, nervousness is not sufficient to justify a pat frisk search. Commonwealth v. Davis, 41 Mass. App. Ct. 793, 796 (1996) (holding that vehicle infraction combined with nervousness and agitation not sufficient to justify protective search). See Delaware v. Prouse, 440 U.S. 648, 657 (1979); United States v. Chavez-Valenzuela, 268 F.3d 719, 728 (9th Cir. 2001).
Pinkes testified at the motion hearing that he did not even remember whether the defendant gave him the vehicle registration. Pinkes was not concerned with which possible explanations were suggested by the facts presented to him. He immediately called for a canine search. Such a reflexive response, particularly in comparison with the step-by-step escalation in Sinforoso, was not supported by articulable facts. See Commonwealth v. Sinforoso, supra at 323-324.
All the evidence at issue on appeal is traceable to the exploitation of the primary illegality — the unlawful detention of the defendant until the drug-detecting dog arrived at the scene. Thus, the seizure of the cocaine from the trunk should have been suppressed as fruit of the poisonous tree. See Commonwealth v. McCleery, 345 Mass. 151, 153-154 (1962); Commonwealth v. Conway, 2 Mass. App. Ct. 547, 553-554 (1974). The discovery by lawful means (and we do not so decide) of the cocaine inside the trunk’s compartment was not “certain as a practical matter,” Commonwealth v. O’Connor, 406 Mass. 112, 117 (1989). Accordingly, I would reverse the judge’s order denying the motion to suppress.
though not well developed at the motion hearing, there was a suggestion that the passenger possessed an international driver’s license which was inside his luggage in the trunk of the vehicle.