The defendant is charged with unlawfully carrying a firearm, G. L. c. 269, § 10(a), and possession of marihuana, G. L. c. 94C, § 34. The Commonwealth appeals *302 from an order of a judge of the Boston Municipal Court allowing the defendant’s pretrial motion to suppress the firearm and the marihuana. These had been seized, according to the judge’s findings, in the following circumstance.
About 11:00 p.m. on the evening of July 4, 1985, Boston police Officer Carl Nemes and his partner, patrolling in a cruiser, received a radio dispatch telling them to be on the lookout for a blue Pinto hatchback automobile driven by a white man and bearing Massachusetts registration 735-KLW. The driver, according to the dispatch, “had pointed a handgun, perhaps an automatic weapon, at a group of citizens at Marlborough and Arlington Streets.” The Pinto was said to be heading outbound on Arlington Street. Officer Nemes, who was nearby, drove the cruiser on what he hoped would be an interception course and within five minutes was passed by a blue Pinto headed in the opposite direction. The registration plate number matched the broadcast. Officer Nemes did a U-turn and followed the Pinto, radioing for assistance. Two other cruisers arrived and together, forming a box around the Pinto, they forced it to the roadside and stopped it. Officer Nemes drew his service revolver and approached the driver’s door, ordering the defendant out. The defendant complied. Through the open door Officer Nemes saw an automatic weapon on the floor on the driver’s side. He arrested the defendant and seized the firearm. (The marihuana was found in the defendant’s left sock later, at the police station, through an inventory search.)
It is apparent from the record that the judge read Commonwealth v. Bottari, 395 Mass. 777 (1985), as requiring him to rule, on these facts, that the stop of the defendant’s vehicle by boxing it in and the approach at gunpoint constituted an arrest, dependent for its validity on antecedent probable cause, and that it could not be justified as a Terry stop, 1 which would require only a reasonable and articulable suspicion. We do not think that the Bottari decision established an inflexible rule to that effect, and, accordingly, we reverse.
*303 In the Bottari case the Boston police had received a report from an informant 2 that Bottari was carrying a handgun unlawfully and that he could be found at a certain shopping center parking lot in Somerville. His car was particularly described. The Boston police notified the Somerville police, whose officers, some two and a half hours later, went to the lot and saw the car. After a wait of another three quarters of an hour or an hour, Bottari and his companions, not acting suspiciously, approached and entered the parked car. The officers blocked off the car and ordered the men out at gunpoint. The officers then searched the glove compartment and the trunk of the car, where they found unlawful weapons. The Supreme Judicial Court sustained a finding by the trial judge that in these circumstances the stop amounted to an arrest. The decision emphasized that, on the judge’s findings, the officers did not fear for their safety or the safety of others at the time they approached the car with guns drawn, and that a different result might be reached in “the presence of other fear-provoking circumstances which are absent here.” 395 Mass, at 782.
It is important to observe that the
Bottari
decision did not purport to be laying down a special rule, under the Massachusetts Constitution, more restrictive of
Terry
stops than that formulated in Federal cases decided under analogous provisions of the United States Constitution. To the contrary, the
Bottari
decision cited and relied on Federal decisions
(United States
v.
Strickler,
The Jackson case is representative of a well established line of Federal authority holding that the boxing in of a moving vehicle and approach by the police at gunpoint do not as matter of law vitiate a justification of the stop under Terry principles. Obviously such stops are highly intrusive. The pertinent inquiry is whether the degree of intrusiveness is reasonable in all the circumstances.
In
United States
v.
Hensley,
In
United States
v.
Jones,
In
United States
v.
Jackson, supra,
police officers stopped a car headed outbound from the scene of a bank robbery which
*305
had taken place five minutes earlier. The driver looked similar in age and complexion to the reported robber
4
and seemed purposefully unconcerned with the police activity around him. The stop of the vehicle and the approach with a drawn gun were held not to convert the stop into an arrest. “Although the drawing of a weapon may be a significant factor in determining whether a suspect is under arrest, it is not dispositive of the issue.”
Thus, proceeding from the Fourth Amendment’s overriding command of reasonableness, both Federal and State cases have recognized the right of police officers to adapt to the special public safety considerations that characterize car stops. These considerations are several. First, “[a] motorist does not have the same communicative potential with a police officer [that] a pedestrian has. The pedestrian being in more or less face-to-face contact with the confronting officer is able to assess the officer’s purpose and determine whether he is free to continue on his way. The motorist, however, is effectively separated from anyone who is not in his automobile.”
People
v.
Lang, 66
Ill. App. 3d 920, 924 (1978). Second, when an officer in a patrol car motions a suspect to pull over, the suspect, particularly if guilty of serious crimes, might flee, starting a high-speed chase endangering bystanders over a wide area. See, e.g.,
United
*306
States
v.
Harley,
Cognizant of these special public safety considerations, courts have held that the boxing in of a vehicle is only one factor to consider in determining whether a car stop constitutes an arrest,
United States
v.
Vargas,
The distinguishing feature of a
Terry
stop is that the intrusion is temporary, and in degree it is not excessive or incommensurate with the accomplishment of its purpose.
Florida
v.
Royer,
We turn then to the question whether the blocking of the defendant’s car and the approach by an officer with a gun drawn was so intrusive as to be tantamount to an arrest. Resolution of this question, by its nature, must depend upon the particular facts of each case.
United States
v.
Ceballos,
We start from the proposition, conceded by the defendant (see note 2, supra), that the police had grounds for a Terry stop. 6 The radio dispatch, corroborated in significant part by the presence of the defendant’s car traveling outbound minutes after the report, indicated the possible commission of two serious crimes: carrying a handgun unlawfully, which, under a well *308 publicized Massachusetts law (G. L. c. 269, § 10[a]), guarantees a minimum mandatory sentence of a year in prison, and assault with a dangerous weapon, which, under G. L. c. 265, § 15B(h), carries a term of up to five years in a State prison. The certainty of imprisonment if guilt was established made flight a realistic possibility. The defendant’s reported behavior was indicative of impulsiveness. In the circumstances it is not reasonable to find that the police used excessive force by anticipating the possibility of flight and guarding against it by boxing in the defendant’s car.
An approach with drawn guns is generally thought excessive in the absence of any suggestion that the defendant is armed or other circumstances suggesting the possibility of violence. Here, the defendant not only had been reported to be armed, possibly with an automatic weapon (as turned out to be the fact) but, in a point that distinguishes this case sharply from the facts in Bottari, he was reported to have drawn the weapon and, inferentially, threatened a group of persons with it, only minutes prior to the stop. The police could not calibrate finely the danger they were facing in approaching the car, but, in our view, on the limited leads they had, the police officers were fully justified in preparing for the worst case: an impulsive, possibly violent resistance to arrest by one armed with an automatic weapon whose motions were largely obscured from their view. Until the defendant was out of the car 7 with hands raised, the risk justified the officer’s approaching the driver’s door with his revolver drawn and aimed. The intrusion was obviously great, but it was momentary in duration and, under the rule of proportionality, was not excessive to the risk *309 the officer was facing at that moment. The intrusiveness did not, therefore, exceed the scope of a Terry-type stop. 8
It follows that the seizure of the automatic weapon was lawful, as it lay on the floor of the car, in plain view through the open door.
Commonwealth
v.
Moynihan,
The order allowing the defendant’s motion to suppress is reversed, and the case is remanded for trial.
So ordered.
Notes
Terry
v.
Ohio,
The court in
Bottari
held that the report did not amount to probable cause under the standards of art. 14 of the Declaration of Rights of the Massachusetts Constitution, as defined in
Commonwealth
v.
Upton,
The same was implicitly held in
Commonwealth
v.
Riggins,
The officers soon realized that he differed in weight and clothing. The man described in the broadcast report was hiding in the trunk.
The
Ballou
case was not overruled by the
Bottari
case but was distinguished on its facts.
See Bottari,
The concession makes it unnecessary for us to consider whether the dispatcher’s testimony might otherwise have been necessary to establish the grounds for the stop. See
Commonwealth
v.
Antobenedetto,
In
Pennsylvania
v.
Mimms,
Subsequent to the argument of this appeal, the Supreme Judicial Court decided
Commonwealth
v.
Sanderson,
The judge did not make a finding that the inventory search of the defendant’s person at the police station was conducted in accordance with standard police procedures, see
Commonwealth
v.
Wilson,
