The defendant Peck entered a plea of guilty to the charge of possession of a controlled substance but preserved his appeal from the denial of his motion to suppress the evidence of the seizure of the plastic bag from his person. G.S. § 15A-979(b) provides a right of appeal from a plea of guilty following denial of a motion to suppress. Defendant contends that the Court of Appeals erred in affirming the trial judge’s denial of his motion to suppress because, he contends, the evidence reveals that the item sought to be suppressed was the fruit of an unlawful search and seizure. We cannot agree. We have carefully reviewed the opinion of the majority of the panel below and the briefs and authorities relating to defendant’s contentions. We conclude that the result reached by the Court of Appeals, its reasoning, and the legal principles enunciated by it are correct, and we adopt that opinion as our own.
We find Sibron v. New York 1 cited in the dissent to be clearly distinguishable. Sibron was convicted of the unlawful possession of heroin. He moved before trial to suppress the heroin seized from his person by the arresting officer, Brooklyn Patrolman Anthony Martin. After the trial court denied his motion, Sibron pled guilty to the charge, preserving his right to appeal the evidentiary ruling. At the hearing on the motion to suppress, Officer Martin testified that while he was patrolling his beat in uniform on March 9, 1965, he observed Sibron “continually from the hours of 4:00 p.m. to 12:00, midnight ... in the vicinity of 742 Broadway.” He stated that during this period of time he saw Sibron in conversation with six or eight persons whom he (Patrolman Martin) knew from past experience to be narcotics addicts. The officer testified that he did not overhear any of these conversations, and that he did not see anything pass between Sibron and any of the others. Late in the evening Sibron entered a restaurant. Patrolman Martin saw Sibron speak with three *736more known addicts inside the restaurant. Once again, nothing was overheard and nothing was seen to pass between Sibron and the addicts. Sibron sat down and ordered pie and coffee, and, as he was eating, Patrolman Martin approached him and told him to come outside. Once outside, the officer said to Sibron, “You know what I am after.” According to the officer, Sibron “mumbled something and reached into his pocket.” Simultaneously, Patrolman Martin thrust his hand into the same pocket, discovering several glassine envelopes, which, it turned out, contained heroin.
The prosecutor’s theory at the hearing was that Patrolman Martin had probable cause to believe that Sibron was in possession of narcotics because he had seen him conversing with a number of known addicts over an eight-hour period. In the absence of any knowledge on Patrolman Martin’s part concerning the nature of the intercourse between Sibron and the addicts, however, the trial court was inclined to grant the motion to suppress. As the judge stated, “All he knows about the unknown men: They are narcotics addicts. They might have been talking about the World Series. They might have been talking about prize fights.” The prosecutor, however, reminded the judge that Sibron had admitted on the stand, in Patrolman Martin’s absence, that he had been talking to the addicts about narcotics. Thereupon, the trial judge changed his mind and ruled that the officer had probable cause for an arrest.
Patrolman Martin did not urge that when Sibron put his hand in his pocket, he feared that he was going for a weapon and acted in self-defense.
In Sibron the District Attorney confessed error and although the Supreme Court acknowledges that “Confessions of error are, of course, entitled to and given great weight,” it found that the confession of error did not relieve the Court of the performance of the judicial function and proceeded to decide the case on the merits. The Court, with regard to the confession of error said:
The prosecution has quite properly abandoned the notion that there was probable cause to arrest Sibron for any crime at the time Patrolman Martin accosted him in the restaurant, took him outside and searched him. The officer was not acquainted with Sibron and had no information concerning him. *737He merely saw Sibron talking to a number of known narcotics addicts over a period of eight hours. It must be emphasized that Patrolman Martin was completely ignorant regarding the content of these conversations, and that he saw nothing pass between Sibron and the addicts. So far as he knew, they might indeed ‘have been talking about the World Series.’ The inference that persons who talk to narcotics addicts are engaged in the criminal traffic in narcotics is simply not the sort of reasonable inference required to support an intrusion by the police upon an individual’s personal security.
392 U.S. at 62, 20 L.Ed. 2d at 934.
The Court concluded that Patrolman Martin’s search of Sibron was unreasonable, that the evidence of the heroin seized was inadmissible, and, since the officer lacked probable cause for Sibron’s arrest, the search could not be justified as incident to a lawful arrest.
In the case before us, the facts may be summarized as follows: On 23 March 1980, at approximately 8:00 p.m., Jess Shelton, a security officer at Western Carolina University, stopped a vehicle which he observed with tires squealing and dust flying. He stopped the vehicle to check the reason for the way it was being driven. He called North Carolina Highway Patrol Officer Cruzan for assistance because he (Shelton) was the only officer on duty at the time and he had orders not to leave the campus except in an emergency. By the time Patrolman Cruzan arrived, Officer Shelton had the driver of the vehicle, a Mr. Parker, in his vehicle. Upon arrival, Patrolman Cruzan asked Shelton if he had checked the passenger in the car. Upon being informed that he had not done so but that it looked like the passenger was intoxicated, Patrolman Cruzan approached the Parker vehicle and observed Mr. Peck inside the car on the passenger side. Officer Shelton testified that he went up to the Parker vehicle right behind Patrolman Cruzan, and that Patrolman Cruzan said to him, “Help me get him out of here.” Officer Shelton testified that he (Shelton) thought that Peck had a gun although he did not see one. Officer Shelton further testified that he thought Peck had a gun when he (Shelton) got hold of him, and it was at that time that Patrolman Cruzan got a plastic bag from *738Peck. Shelton did not hear all of the conversation between Patrolman Cruzan and Peck.
Patrolman Cruzan testified in effect that when he arrived Officer Shelton had the driver, Parker, under arrest for operating the vehicle without a license as his license had been previously revoked. Being informed that the passenger in the vehicle had not been checked, Patrolman Cruzan went to the passenger side of the Parker vehicle, opened the door, and started to talk to Peck who stated, “I’m feeling sick.” Patrolman Cruzan told him to step out of the car if he was going to throw up, to which Peck replied, “I’m not going to throw up, I just don’t feel good.” Patrolman Cruzan then squatted down beside Peck. He observed the faint odor of an alcoholic beverage and saw that Peck’s pupils were dilated, that his eyes were red, that his mouth had mucus on the corner of it and that he was “kind of cotton mouthed.” Patrolman Cruzan said to Peck, “Son, do you have dope in here or on you?” At that time, Peck leaned back and stuck his left hand down in the front of his pants. When he did that Patrolman Cruzan grabbed his hand and jerked it out of his pants. For the first time, Cruzan could see in plain view the corner of a plastic bag sticking out of the defendant’s pants where his hand had been. Patrolman Cruzan and Officer Shelton got Peck out of the vehicle. Cruzan held Peck’s hands behind his back and reached around in front of Peck and pulled the plastic bag out of Peck’s pants. The bag contained a white powdery substance later identified as the controlled substance methylenedioxyamphetamine (MDA). Officer Cruzan testified that he did not know when he saw Peck reach into his pants what was in his pants. He advised Peck of his constitutional rights and proceeded to search the rest of the vehicle. Cruzan testified on cross-examination, as narrated in the record before us, “that he had no reason to believe that the Defendant was going for a weapon.”
There are certain similarities between this case and Sibron: (1) In both cases the defendant entered a plea of guilty but preserved his appeal on the denial of his motion to suppress the evidence of the drugs seized, (2) Highway Patrolman Cruzan’s question to Peck as to whether he had any drugs is similar to Patrolman Martin’s statement to Sibron that “You know what I am after,” (3) drugs were taken from the person of both Peck and Sibron, and (4) at least ostensibly, neither officer’s actions *739resulted from a self-protective search for weapons. Sibron is otherwise completely dissimilar.
Sibron involved a situation in which the police officer without just cause accosted the defendant in a public restaurant and brought him outside onto the public street where the “search” was conducted for no other purpose than an attempt to find drugs. In the incident before us in this case there was a roadside arrest of the driver of a vehicle in the night-time. In checking the stopped vehicle and its passenger, Patrolman Cruzan observed that the passenger, defendant Peck, had red eyes, dilated pupils and mucus on the corner of his mouth; he appeared cotton-mouthed and said he felt sick. After Cruzan’s investigatory question concerning whether Peck had drugs on him or in the vehicle, Peck leaned back and thrust his hand into his pants. In what appears to have been an instinctive reflex reaction, Cruzan grabbed his arm. Clearly, Patrolman Cruzan’s reaction to Peck’s furtive movement in seizing Peck’s arm was reasonable as a self-protective measure.
We would no doubt have little difficulty in finding grounds for a protective search had Patrolman Cruzan been able to articulate for instance that there was a bulge in the defendant’s pants or shirt which he believed to be a gun. Here the defendant’s pants could certainly have concealed a knife, razor, or similar small but dangerous weapon. The point is, when a subject makes a furtive gesture or suspicious movement as here, the officer more often than not reacts instinctively to protect himself and others without reasoning as to whether there is an “ar-ticulable reason” or “founded suspicion.” Perhaps the officer can articulate his reasons after the fact and upon reflection and perhaps he cannot. Perhaps he can later articulate nothing more than a common-sense instinct or conclusion about human behavior gained from experience. We must constantly remind ourselves that we examine the circumstances “after the fact” with much consideration and with hindsight in the calm and safety of a courtroom.
Crimes of violence are on the increase, and officers are becoming the victims of such crimes in increasing numbers. As a result the necessity for officers to protect themselves and others in situations where probable cause for an arrest *740may be lacking is now recognized and permitted. Of course, North Carolina has no ‘stop and frisk’ statute although many states do. See Raphael, ‘Stop and Frisk’ in a Nutshell: Some Last Editorial Thrusts and Parries Before It All Becomes History, 20 Ala. L. Rev. 294 (1968). The lack of such statute, however, is not fatal to the authority of law enforcement officers in North Carolina to stop suspicious persons for questioning (field interrogation) and to search those persons for dangerous weapons (frisking). These practices have been a time-honored police procedure and have been recognized as valid at common law ‘as a reasonable and necessary police authority for the prevention of crime and the preservation of public order.’ People v. Rivera, 14 N.Y. 2d 441, 252 N.Y.S. 2d 458, 201 N.E. 2d 32 (1964), and authorities cited. See also, United States v. Vita, 294 F. 2d 524 (2d cir. 1961); Cook, Detention and the Fourth Amendment, 23 Ala. L. Rev. 387 (1970-71); LaFave, ‘Street Encounters’ and the Constitution: Terry, Sibron, Peters and Beyond, 67 Mich. L. Rev. 40 (1968). Since the common law, unless abrogated or repealed by statute, is in full force and effect in this State, G.S. 4-1, the absence of statutory authority to stop and frisk does not render these common law practices illegal in our State.
Nor does the Federal Constitution prohibit them when they are reasonably employed. In Terry v. Ohio, 392 U.S. 1, 20 L.Ed. 2d 889, 88 S.Ct. 1868 (1968), the Court held, among other things, that ‘the central inquiry under the Fourth Amendment [is] the reasonableness in all the circumstances of the particular governmental invasion of a citizen’s personal liberty. * * * [W]e cannot blind ourselves to the need for law enforcement officers to protect themselves and other prospective victims of violence in situations where they may lack probable cause for an arrest. When an officer is justified in believing that the individual whose suspicious behavior he is investigating at close range is armed and presently dangerous to the officer or to others, it would appear to be clearly unreasonable to deny the officer the power to take necessary measures to determine whether the person is in fact carrying a weapon and to neutralize the threat of physical harm.’
*741The Court then recognized that it is not always unreasonable to seize a person and subject him to a limited search for weapons where there is no probable cause for an arrest, stating: ‘[W]here a police officer observes unusual conduct which leads him reasonably to conclude in light of his experience that criminal activity may be afoot and that the persons with whom he is dealing may be armed and presently dangerous, where in the course of investigating this behavior he identifies himself as a policeman and makes reasonable inquiries, and where nothing in the initial stages of the encounter serves to dispel his reasonable fear for his own or others’ safety, he is entitled for the protection of himself and others in the area to conduct a carefully limited search of the outer clothing of such person in an attempt to discover weapons which might be used to assault him.’ Terry v. Ohio, supra.
Thus, if the totality of circumstances affords an officer reasonable grounds to believe that criminal activity may be afoot, he may temporarily detain the suspect. If, after the detention, his personal observations confirm his apprehension that criminal activity may be afoot and indicate that the person may be armed, he may then frisk him as a matter of self-protection. Terry v. Ohio, supra See Adams v. Williams, 407 U.S. 143, 32 L.Ed. 2d 612, 92 S.Ct. 1921 (1972).
State v. Streeter, 283 N.C. 203, 209-10, 195 S.E. 2d 502, 506-07 (1973).
It does not matter that subjectively Cruzan had no reason to believe that Peck had a gun. “[T]he scope of the Fourth Amendment is not determined by the subjective conclusion of the law enforcement officer.” United States v. Clark, 559 F. 2d 420 (5th Cir. 1977), cert. denied, 434 U.S. 969, 98 S.Ct. 516, 54 L.Ed. 2d 457 (1977), quoting United States v. Resnick, 455 F. 2d 1127 (5th Cir. 1972). The officer’s subjective opinion is not material. Nor are the courts bound by an officer’s mistaken legal conclusion as to the existence or non-existence of probable cause or reasonable grounds for his actions. The search or seizure is valid when the objective facts known to the officer meet the standard required. See Scott v. United States, 436 U.S. 128, 98 S.Ct. 1717, 56 L.Ed. 2d 168, reh’g denied, 438 U.S. 908, 98 S.Ct. 3127, 57 L.Ed. 2d 1150 *742(1978); United States v. Bugarin-Casas, 484 F. 2d 853 (9th Cir. 1973), cert. denied, 414 U.S. 1136, 94 S.Ct. 881, 38 L.Ed. 2d 762 (1974); Klingler v. United States, 409 F. 2d 299 (8th Cir. 1969), cert. denied, 396 U.S. 859, 90 S.Ct. 127, 24 L.Ed. 2d 110 (1969); State v. Vaughn, 12 Ariz. App. 442, 471 P. 2d 744 (1970); People v. Baird, 172 Colo. 112, 470 P. 2d 20 (1970), citing Sirimarco v. United States, 315 F. 2d 699 (10th Cir. 1963), cert. denied, 374 U.S. 807, 83 S.Ct. 1696, 10 L.Ed. 2d 1032 (1963); State v. Vanzant, 14 Wash. App. 679, 544 P. 2d 786 (1975). See generally 1 W. LaFave, Search and Seizure, A Treatise on the Fourth Amendment §§ 1.2(g), 3.2(b) (1978).
Cruzan testified that he did not know what Peck was reaching for in his pants. The test of “whether a reasonably prudent man in the circumstances would be warranted in the belief that his safety or that of others was in danger” is clearly met on the facts before us. Terry v. Ohio, 392 U.S. 1, 27, 88 S.Ct. 1868, 1883, 20 L.Ed. 2d 889, 909 (1968). We are here concerned with whether the conduct of Officer Cruzan negated any of the four elements of the plain view doctrine upon which this case was determined by the trial court and the Court of Appeals. We agree with the Court of Appeals that the four elements of the plain view doctrine as enunciated by the Supreme Court in Coolidge v. New Hampshire, 403 U.S. 443, 91 S.Ct. 2022, 29 L.Ed. 2d 564 (1971), were present. First, Patrolman Cruzan had legal justification to be at the place and in the position he was when he saw the evidence in plain view. Second, the discovery of the evidence was inadvertent as it was discovered incident to removal of the defendant’s hand from his pants and clearly was not the result of a deliberate search. Third, the evidence was immediately apparent and its discovery under the circumstances clearly would warrant a man of reasonable caution in believing that the defendant was in the possession of drugs and was hiding evidence which would incriminate him. Fourth, Patrolman Cruzan’s observation of the defendant’s condition and the sight of part of the plastic bag which contained the white powdery substance was such as to give a reasonable man the belief that there was evidence of criminal activity present, to-wit, the possession of drugs.
The Court of Appeals affirmed the defendant’s conviction and held that the trial court correctly denied defendant’s motion to *743suppress, reasoning that the plain view doctrine was applicable and all elements were present. We agree.
The decision of the Court of Appeals is
Affirmed.