Defendant was convicted for possession of cocaine, ORS 475.992, possession of less than an ounce of marijuana, ORS 475.992, and failure to display a driver’s license. ORS 807.570. He appeals, assigning as error the court’s denial of his motion to suppress evidence seized from his person and car. We affirm.
On December 21,1988, officers Gray and Anderson, members of the Drug and Vice Division of the Portland Police Bureau, were in plain clothes and in an unmarked car with tinted windows when they began following defendant’s car. The officers, who regularly made two or three traffic stops a week in addition to their narcotics duties, decided to stop defendant after he had made several turns without signalling. They testified that they did not suspect him of any other wrongdoing and that they had no other information about him. After the officers activated a portable blue light, defendant pulled his car over. Gray approached the car and asked defendant for his driver’s license. Defendant told Gray that his license was suspended. He was unable to produce any other identification or the car’s registration.
Gray decided to take defendant into custody for failure to display an operator’s license until they could verify his identity. He ordered defendant out of the car while Anderson conducted a records check. As defendant was standing on the sidewalk, Gray asked him if he had any drugs or weapons on his person. Defendant said that he did not. Gray testified that he asked defendant for permission to search his person and that defendant said, “Go ahead.” Defendant testified that Gray searched him without asking permission.
Gray then searched defendant’s person. He testified:
“I started to check his pockets. And I felt something metal like [in] his jacket pocket — his left-pocket jacket, and I had reached in to pull that out. It turned out to be a pair of small — similar to the stainless-surgical scissors.
“And as I pulled it out, I pulled out a real small bundle of marijuana and I asked him about it. And as I was looking at the scissors, I had noticed that there was quite a bit of what appeared to be residue on the scissors; that is consistent to *264me with actually cutting and trimming marijuana from the plants.”
Gray asked, defendant if there was more marijuana in the car. Defendant replied that there was not. Gray asked for permission to search the car. He testified that defendant consented, and the trial court so found. Gray found nothing in his cursory search of the passenger compartment but, when he opened the trunk, he found bags of cocaine and marijuana stuffed into the sleeves of a jacket. He also found a wallet in the trunk with defendant’s identification and $2,700 in cash. As soon as Gray recognized the cocaine, he told Anderson what he had found. They handcuffed defendant and gave him Miranda warnings.
Defendant makes several alternative arguments in support of his position that the court should have granted his motion to suppress. First, he contends that the initial stop of his car was illegal, because it was a “pretext stop.” We have held that, under Article I, section 9, if an officer is where he has a right to be and sees a driver commit a traffic infraction, the officer may stop the driver under ORS 810.410(2), regardless of any other motive that he may have. State v. Olaiz, 100 Or App 380, 383, 786 P2d 734, rev den 310 Or 122 (1990); State v. Zigler, 100 Or App 700, 703, 788 P2d 484 (1990). Defendant committed traffic infractions in the presence of the officers.
Defendant also argues that the stop was unlawful, because ORS 810.400 requires that police officers who enforce traffic laws must either be in uniform or show official identification. Gray and Anderson were not in uniform, and the record is silent on whether they displayed official identification. A violation of ORS 810.400 does not, itself, invalidate a stop. See State v. Chaput, 43 Or App 831, 833, 604 P2d 435 (1979). The stop was lawful.
Defendant also asserts that the police request for consent went beyond the permissible scope of the stop. We disagree. When Gray asked permission to search defendant and his car, defendant was lawfully under arrest for failure to display an operator’s license. We have held that
“[a]n officer may request consent to search from a party lawfully in custody, and the request need not relate to the *265crime for which the party was arrested.” State v. Auer, 90 Or App 459, 464, 752 P2d 1250 (1988).
The offense for which the officers arrested defendant did not limit the scope of Gray’s request for consent to search.
The dissent reads State v. Porter, 312 Or 112, 817 P2d 1306 (1991), as preventing Gray from asking defendant for his consent to search the car. Porter does hold that, when a person is stopped only for a traffic infraction, the police may not instigate a search ‘ ‘unless it has some basis other than the traffic infraction.” However, it does not hold that an officer in such circumstances may not ask for consent. No justification is necessary for an officer to ask for consent. Consent may be requested following illegal police conduct, State v. Williamson, 307 Or 621, 772 P2d 404 (1989), or of a citizen on the street. Neither the statute nor Porter imposes such a limitation on officers conducting stops for traffic infractions, and it would make no sense to do so.
Defendant also contends that the circumstances of the stop and the request to search his person and car were so coercive that, even if he consented to the searches, his consent was involuntary. The trial court did not rule on whether defendant consented to the search of his person, because it held that that search was valid as a search incident to arrest. We conclude that that was a proper basis for the search of his person. A person under full custodial arrest, as defendant was, may be searched incident to the arrest to protect officer safety or to preserve evidence of the crime from destruction or concealment. State v. Owens, 302 Or 196, 200, 729 P2d 524 (1986). A pat-down or limited search for weapons to protect the officer is justified whenever a person is taken into custody. State v. Owens, supra, 302 Or at 200; State v. Smith, 103 Or App 113, 116, 796 P2d 665 (1990), rev allowed 311 Or 87 (1991). The record indicates that the officer conducted a pat-down of defendant’s jacket and that he felt something metallic that could have been a weapon. He was then justified in reaching into the pocket to identify the object. When he did that, he removed both the scissors and the small amount of marijuana.
With respect to the search of the car, the trial court found that defendant did consent and concluded that the *266consent was voluntary. We review the facts to assess whether they meet constitutional standards of voluntariness. State v. Stevens, 311 Or 119, 135, 806 P2d 92 (1991). The state must prove voluntary consent by a preponderance of the evidence. State v. Stevens, supra, 311 Or at 137. We judge voluntariness in the light of the totality of the circumstances to see whether the consent was given by defendant’s free will or was the result of coercion, express or implied. State v. Kennedy, 290 Or 493, 502, 624 P2d 99 (1981).
We conclude that the state carried its burden of proving that defendant’s consent to search his car was voluntary. There was nothing coercive about the encounter. Anderson described defendant as cooperative and the encounter as “low key.” There was no testimony that the officers threatened defendant in asking for consent to search his car. Defendant argues that the fact that he did not know, when they began following him, that Anderson and Gray were police officers made the encounter coercive. However, even assuming that that added some element of coerciveness to the situation, the record shows that defendant knew that they were police officers before he consented to the search of his car. We conclude from the totality of circumstances that his consent was voluntary. The trial court properly denied the motion to suppress.
Affirmed.