At issue is the propriety of a stop and patfrisk of the defendant. On appeal from his convictions of illegal possession of a firearm and ammunition, the defendant maintains that the motion judge erred in denying his motion to suppress the loaded handgun found by the police. We conclude that the stop, frisk, and seizure exceeded constitutional bounds.
1. Facts. We take the facts from the motion judge’s findings *399and the undisputed testimony.1 See Commonwealth v. Hinds, 437 Mass. 54, 55 (2002), cert. denied, 537 U.S. 1205 (2003). Shortly after midnight on April 27, 2005, Officers John Conway and Dean Bickerton of the Boston police department were riding in an unmarked Ford Crown Victoria automobile in the vicinity of Babson and Delhi Streets in the Dorchester section of Boston. That locale is a “high crime” area where, on past occasions, shots had been fired and arrests had been made involving illegal handguns.
Conway and Bickerton had three years’ experience each. Their prior police academy training included consideration of the ways in which individuals conceal and transport firearms. One such method — the straight arm method — employs a straightened arm pressed against the concealed weapon. Ten to fifteen percent of their twenty-five gun arrests in the previous eight months involved an initial observation of this method of carrying the firearm.
As Bickerton drove along Delhi Street, he and Conway observed the defendant walking along the sidewalk and talking on his cellular telephone, which he held in his left hand. The defendant’s right arm was rigid, not moving, and pressed to his side as if he were holding something. Believing that the defendant’s manner of walking warranted investigation, the officers turned the car around. As they approached the defendant, who was now on Babson Street, they observed that he continued to walk favoring his right side.
Without activating the vehicle’s blue lights or siren, Bicker-ton pulled the vehicle alongside the defendant2 and hailed him by a name chosen at random.3 Through the driver’s side window, Bickerton asked the defendant if he was from the area, where he was coming from, and where he was going. The officers, who were dressed in plain clothes with badges displayed at *400chest level, noticed that the defendant was attempting to shield his right side from their view “as if trying to hide something.” He avoided eye contact, looked left and right, and shifted his weight from side to side.
Concerned that the defendant was about to run, Bickerton stepped out of the car and approached him. The defendant told the officers that he lived in New York, but was staying with his family at an apartment on Delhi Street.4 To dispel the mistaken belief that he was “Dwayne,” the defendant reached into his right pants pocket and produced identification, which he gave to Bickerton, who was an arm’s length away.5 Conway then ran the identifying information through the vehicle’s mobile computer with negative results for warrants or incriminating information.
As the defendant reached into his right pants pocket for identification, the officers noted that he continued to turn his right side from their view. They also observed that the right pocket of his jacket was tilted to the side, as if it held a heavy object — heavier than a cellular telephone, wallet, or pack of cigarettes. Believing that the defendant’s jacket contained a firearm, Bickerton told the defendant that he intended to conduct a patfrisk.6 As Bickerton moved to frisk him, the defendant moved back to avoid being frisked. The officers told the defendant that they wanted to conduct a patfrisk for his safety as well as their own, and Bickerton again moved towards him. As the defendant again attempted to move away, Bickerton *401grabbed the defendant’s right jacket pocket and felt the handle of a handgun. He reached into the defendant’s pocket and seized the gun.7
2. Discussion. Assessment of witness credibility is the province of the motion judge. See Commonwealth v. Yesilciman, 406 Mass. 736, 743 (1990), and cases cited; Commonwealth v. Gutierrez, 26 Mass. App. Ct. 42, 47 (1988). We accept the judge’s subsidiary findings of fact absent clear error, but conduct an independent review of his ultimate findings and conclusions of law. See Commonwealth v. Jimenez, 438 Mass. 213, 218 (2002). “[O]ur duty is to make an independent determination of the correctness of the judge’s application of constitutional principles to the facts as found.” Commonwealth v. Scott, 440 Mass. 642, 646 (2004), quoting from Commonwealth v. Mercado, 422 Mass. 367, 369 (1996).
We conclude that the judge erred in his application of law to the facts found. See Commonwealth v. Vesna San, 63 Mass. App. Ct. 189, 190 (2005). Whether viewed from the standpoint of reasonable suspicion of criminal activity or that of reasonable apprehension of danger, the stop and immediate patfnsk of the defendant is not constitutionally supportable.8
a. Reasonable suspicion of criminal activity. A field encounter is not a constitutional stop. See Commonwealth v. Stoute, 422 Mass. 782, 785-789 (1996). “[O]fficers may make inquiry of anyone they wish and knock on any door, so long as they do not implicitly or explicitly assert that the person inquired of is not free to ignore their inquiries.” Commonwealth v. Murdough, 428 Mass. 760, 763 (1999). At the same time, a tenuous balance exists between mere encounters and unconstitutional conduct. Citizens do not expect that police officers, whether handling routine traffic violations or engaging in casual street encounters, “will engage, in the absence of justification, in stalling tactics, obfuscation, [or] strained conversation” in the hope that sooner or later evidence of an arrestable offense will *402turn up. Commonwealth v. Gonsalves, 429 Mass. 658, 663 (1999). From a citizen’s perspective such encounters may be rightfully viewed as nothing more than an arrogant and unnecessary approach to the constitutional line. Such encounters “may also pose unique hardships on minorities who, it has been argued, are often the subject of stops on pretext.” Ibid.
Here, the officers’ initial interaction with the defendant approached, but did not exceed, the boundary of a stop within the meaning of the Fourth Amendment to the United States Constitution or art. 14 of the Massachusetts Declaration of Rights. Compare California v. Hodari D., 499 U.S. 621, 624-626 (1991) (stop occurs for Fourth Amendment purposes when police apply force or make show of authority to which subject yields); Commonwealth v. Stoute, 422 Mass. at 785-789 (adopting “free to leave” standard of United States v. Mendenhall, 446 U.S. 544, 554 [1980], for art. 14 purposes). The officers did not employ the talismans of blue lights, flashers, or sirens, or use words of command to cause the defendant to stop walking. See Commonwealth v. Grandison, 433 Mass. 135, 138 (2001). Their tone was conversational, not authoritative; they employed no weapons or other indicia of authority from which, at least as a matter of constitutional analysis, a reasonable person would not feel free to leave the encounter. See Commonwealth v. Rock, 429 Mass. 609, 612 (1999) (officer’s intent to stop defendant not relevant to “free to leave” analysis, absent outward manifestation of that intent). Compare Commonwealth v. Barros, 435 Mass. 171, 174-176 (2001) (officer’s second request to stop had “compulsory dimension” that first did not).
The Commonwealth concedes, correctly, that a stop for art. 14 purposes occurred when the officers declared their intent to frisk the defendant, as he was then no longer free to leave. See ibid. Contrary to the Commonwealth, however, we conclude that at that point of constitutional moment, the officers lacked reasonable suspicion that the defendant might be engaged in criminal activity. At that time, there was no objective factual basis for concluding that the defendant possessed a firearm, much less an unlicensed one. See id. at 177.
Prior to encountering the defendant, the officers had neither observed nor received any report of criminal activity, a firearm *403being brandished, or shots being fired. Compare Commonwealth v. Fraser, 410 Mass. 541, 546 (1991); Commonwealth v. Foster, 48 Mass. App. Ct. 671, 676-677 (2000); Commonwealth v. Johnson, 49 Mass. App. Ct. 273, 275 (2000). That the defendant was walking in an area not unfamiliar with firearm violence is a factor in assessing reasonable suspicion of criminal activity. “But this factor must be considered with some caution because many honest, law-abiding citizens Uve and work in high-crime areas. These citizens are entitled to the protections of the Federal and State Constitutions, despite the character of the area.” Commonwealth v. Holley, 52 Mass. App. Ct. 659, 663 (2001). The officers had no prior knowledge of, or dealings with, the defendant that would provide a basis for ascribing criminality to his actions. His activities do not take on a sinister cast merely because the street on which he is walking is located in Dorchester. See Commonwealth v. Cheek, 413 Mass. 492, 496-497 (1992) (problems facing “ ‘high crime area’ will not be resolved any more readily by excluding the individuals who five there from the protections afforded by our Constitution”).
What the case for singling out this defendant hinges on is the manner in which he was walking — with an arm rigid and pressed against his right side. The Commonwealth contends that the officers’ training and experience provided a basis for believing criminal activity was afoot because the defendant’s manner of walking was characteristic of that employed by people who carry concealed firearms illegally. According to the Commonwealth, the defendant’s walk, coupled with his subsequent nervousness, avoiding of eye contact, shifting from side to side, and shielding of his right jacket pocket (which contained a heavy object) from the officers’ view, created a reasonable suspicion that he was carrying a concealed firearm and was not licensed to do so. We disagree.
We acknowledge that an officer’s training and experience can be an important factor. See Commonwealth v. Kennedy, 426 Mass. 703, 706 (1998); Commonwealth v. Peters, 48 Mass. App. Ct. 15, 17-18 (1999). We are unpersuaded, however, that the manner of the defendant’s walk, even in conjunction with the other cited factors, provided an objective factual basis for a reasonable suspicion that the defendant was engaged in criminal *404activity (or, as discussed infra, posed a danger). The observed activity, walking with an arm pressed closely to the side, is fundamentally different from that described in Kennedy as fitting a “pattern” or “archetype” consistent with a “classic street level drug transaction.” Notably absent here, but present in Kennedy, is prior knowledge of previous involvement in the criminal conduct at issue, thereby providing context for viewing with a skeptical eye what might otherwise appear to be innocuous conduct. Commonwealth v. Kennedy, supra at 706-707. So too, in Commonwealth v. Watson, 430 Mass. 725, 729-731 (2000), cited by the dissent, post at 409, the defendant’s association with an individual whose actions satisfied the indicators for a drug dealer provided the critical context for ascribing criminality to a number of seemingly innocent activities.
An individual’s manner of walking, like his hairstyle or clothing, is by itself too idiosyncratic to serve as the basis for a reasonable suspicion of criminal activity. See Commonwealth v. Heon, 44 Mass. App. Ct. 254, 256 (1998). Absent context for characterizing the defendant’s action as bearing a criminal cast, there are too many innocent explanations to permit idiosyncracy to serve as the critical identifier of criminal conduct. See Commonwealth v. Houle, 35 Mass. App. Ct. 474, 476-477 (1993) (officer’s specialized knowledge, even together with defendant’s appearance, did not amount to particularized suspicion defendant engaged in criminal activity).9
The Commonwealth makes much of the fact that besides walking as he did, the defendant also continually positioned himself to keep his right side out of the officers’ view. That such activity undoubtedly provides reason for vigilance does not add enough to amount to reasonable suspicion of criminal activity. “There is no suspicious conduct except as the concealment itself may generate suspicion.” Commonwealth v. Alvarado, 423 Mass. 266, 270 (1996). The defendant made no furtive gestures. See Commonwealth v. Holley, 52 Mass. App. Ct. *405at 663-665; Commonwealth v. Hooker, 52 Mass. App. Ct. 683, 686-687 (2001). He never made a movement to his jacket pocket or his waistband, factors that in other contexts have given rise to a reasonable apprehension of danger. Compare Commonwealth v. Fisher, 54 Mass. App. Ct. 41, 45-46 (2002) (defendant’s reaching for waistband as he walked away from approaching officer justified officer’s belief that his safety and that of other officers was at risk); Commonwealth v. Pagan, 63 Mass. App. Ct. 780, 782-783 (2005) (same). Indeed, the defendant’s movement to retrieve identification from his adjacent pants pocket occurred in ready view of the officers.
Nor do the defendant’s apparent nervousness, lack of eye contact, and shifting from side to side provide the requisite plus factors. Compare Commonwealth v. Santaliz, 413 Mass. 238, 241-242 (1992) (number of individually insufficient factors, taken together, establish basis to believe crime is ongoing); Commonwealth v. Robie, 51 Mass. App. Ct. 494, 497-498 (2001). An individual who is walking alone in a high crime area after midnight might well exhibit nervousness and anxiety when approached by two individuals unknown to him. See Commonwealth v. Hooker, 52 Mass. App. Ct. at 688. Absent other factors not present here, the defendant’s attempt to avoid contact with police, and his other arguably evasive behavior, are inadequate grounds on which to predicate reasonable suspicion that he was carrying a gun. See Commonwealth v. Barros, 435 Mass. at 178; Commonwealth v. Grinkley, 44 Mass. App. Ct. 62, 72 (1997) (attempts to avoid contact with police pertinent to reasonable suspicion determination only if other factors present beyond arguably evasive behavior).
It was the defendant’s right to ignore the officers. To hold otherwise is to invite arbitrary and unequal treatment, see Commonwealth v. Gonsalves, 429 Mass. at 664, or to allow the police to “turn a hunch into a reasonable suspicion by inducing the conduct justifying the suspicion.” Commonwealth v. Barros, supra at 178, quoting from Commonwealth v. Thibeau, 384 Mass. 762, 764 (1981).
Beyond failing to prove that the defendant had a gun in his jacket pocket, the Commonwealth also failed to establish that there existed reasonable suspicion that he lacked a license to do *406so. “[Knowledge] that someone is carrying a gun does not, without more, constitute reasonable suspicion to conduct a stop and frisk of that individual.” Commonwealth v. Barros, supra at 177, citing Commonwealth v. Couture, 407 Mass. 178, 183, cert. denied, 498 U.S. 951 (1990) (“mere possession of a handgun was not sufficient to give rise to a reasonable suspicion that the defendant was illegally carrying that gun”). See Commonwealth v. Alvarado, 423 Mass. at 269-270 (reasonable suspicion not warranted simply on report of gun possession). The officers did not inquire whether he had a license until after they had frisked him and seized the weapon. The driver’s license supplied to the officers was not introduced as an exhibit. Nor did the officers testify regarding the defendant’s age, either as documented in his driver’s license or deduced from his appearance. See Commonwealth v. Barros, 435 Mass. at 179 (Sosman, J., concurring) (defendant’s apparent youth an objective basis for suspecting he is too young to be licensed).10
Contrary to the motion judge’s conclusion that the defendant’s evasive actions were “inconsistent with legal possession,” the Commonwealth bears the burden of proving that at the time of the frisk the police had reasonable suspicion that the defendant possessed a firearm illegally. See Commonwealth v. Franklin, 316 Mass. 885, 898 (1978). This the Commonwealth failed to do.11
b. Reasonable apprehension of danger. We also consider and reject the contention that a frisk was permissible even absent a reasonable suspicion of criminal activity. See Commonwealth v. Foster, 48 Mass. App. Ct. 671, 680 (2000) (Jacobs, J., concurring) (“The inherent dangerousness of guns ... is not diminished by the fact that licensed carrying of a gun is lawful”). Notably absent are factual indicia that would permit *407the police reasonably to conclude that the defendant was armed and dangerous. Compare Commonwealth v. Fraser, 410 Mass. 541, 544-545 & n.4 (1991); Commonwealth v. Fisher, 54 Mass. App. Ct. at 43-47. In Fraser, officers responding to a report of a man with a gun found a group of young men at the reported location, a high crime area. The defendant bent down behind a truck “as though to pick something up or put something down.” Commonwealth v. Fraser, supra at 545. He then confronted an officer with his hands in his pocket. See ibid. In such circumstances, the court recognized, a patfrisk is justified even though the officers lacked sufficient information to justify an investigative stop under Terry v. Ohio, 392 U.S. 1 (1968). Police officers have a duty to investigate potential dangers to the public; and an investigating officer who comes into proximity with the defendant need not place his safety at risk. See Commonwealth v. Fraser, supra at 544 n.4.
Similarly absent is the exigency that existed in Commonwealth v. Foster, 48 Mass. App. Ct. at 673, where a report that a man was “displaying a gun,” in context, provided a reasonable basis for investigating police to conclude that the described individuals were “armed and dangerous” so as to justify a protective frisk. Here, there was no such showing of imminent danger. See Commonwealth v. Alvarado, 423 Mass. at 270; Commonwealth v. Barros, 435 Mass. at 173.
Unlike in Fraser or Foster, Officers Conway and Bickerton were not investigating a report of a man with a gun, a shot, or any crime. Rather, they were pursuing a hunch that the defendant’s walk suggested he was carrying a firearm. “The vice in . . . searches based on a hunch is their essentially random and arbitrary nature, a quality inconsistent, under constitutional norms . . . , with a free and ordered society.” Commonwealth v. Bartlett, 41 Mass. App. Ct. 468, 472 (1996). Based on that hunch, they put themselves in such proximity to the defendant as to claim that his response placed them at risk and required a patfrisk for safety reasons. This is not the kind of emergency that justifies a protective frisk. See Commonwealth v. Barros, supra at 178 (refusing to permit police to turn hunch into reasonable suspicion by inducing conduct justifying suspicion).
*408Apart from the illegal search and seizure, there was no evidence that the defendant possessed a firearm or ammunition illegally. See Commonwealth v. Muckle, 61 Mass. App. Ct. 678, 685 (2004). Accordingly, we reverse the judgments of conviction and order that judgment enter for the defendant on the complaints.
So ordered.
The judge heard from the two arresting police officers and the defendant.
It is unclear from the testimony or from the judge’s findings whether the vehicle was on the wrong side of the road and across the street from the defendant or next to him. The difference is inconsequential. See Commonwealth v. Rock, 429 Mass. 609, 612 (1999) (driving unmarked cruiser on wrong side of one-way street not a stop).
The defendant testified that the officers yelled to him, “Yo, Dwayne.” The officers did not know the defendant; they addressed him by name in order to get closer to him.
The defendant worked in New York in customer service and as a teller, but his parents and brother had an apartment on Delhi Street.
The defendant confirmed that he provided his New York state driver’s license to Bickerton voluntarily. He stated that he also provided a second form of identification, his student identification card from Berkeley College in New York.
The uncontested testimony was that the officers did not ask the defendant whether he had a firearm until after they told him that they were going to conduct a patfrisk. The judge made no explicit factual findings concerning the chronology of the frisk and the officers’ inquiry. See Commonwealth v. Ciaramitaro, 51 Mass. App. Ct. 638, 642 (2001) (emphasizing fact intensive and time dependent nature of search and seizure analysis).
The officers and the defendant dispute whether in response to that question the defendant replied, “I wouldn’t blast you all,” a point on which the judge also made no factual finding. Because the frisk preceded the inquiry regarding the firearm, the defendant’s response, if any, is not material to our analysis.
The defendant told the officers that he was not licensed to possess a firearm.
The motion judge’s legal determination appears to rest primarily on a reasonable apprehension of danger, but includes the alternative view that the defendant’s actions were “inconsistent with legal possession.”
Even in the officers’ experience, only fifteen percent (three or four) of their twenty-five arrests for illegal firearms involved individuals who walked in such a manner. Such a statistical indicator hardly makes reasonable a suspicion that criminal activity is afoot predicated on a manner of walking as opposed to other indicators. See Commonwealth v. Kennedy, 426 Mass. at 708.
The relevant statute now permits issuance of a license to carry a firearm only to persons twenty-one years of age or older. See G. L. c. 140, § 131(á)(iv), as amended by St. 1998, c. 180, § 41.
We have no doubt that a reasonable suspicion that the defendant was carrying a handgun illegally would have provided a basis for conducting a pat-frisk for that reason alone. See Commonwealth v. Gonsalves, 429 Mass. at 664 (where reasonable suspicion exists, “it does not take much for a police officer to establish a reasonable basis to justify ... [a] search based on safety concerns”).