Defendant was convicted of manufacturing a controlled substance, ORS 475.992, after the trial court declined to suppress evidence found in his pickup truck. Police officers found the evidence, marijuana plants in closed boxes, after they unlawfully stopped defendant’s vehicle at a roadblock and defendant acquiesced in a search of the boxes rather than wait for one of the officers to obtain a search warrant. The Court of Appeals held that the evidence should have been suppressed and remanded the case to the circuit court. State v. Williamson, 92 Or App 426, 759 P2d 288 (1988). Having allowed the state’s petition for review, we affirm the decision of the Court of Appeals.
We briefly summarize the facts set out in the court’s opinion. Officers Rupp and Becker stopped defendant’s open-bed pickup truck at a police roadblock to check licenses and vehicle registrations. Recognizing defendant’s name from a drug investigation, Becker stepped toward the rear of the truck, leaned over the truck bed, and smelled what he believed to be marijuana. After directing defendant to park in a nearby lot, Becker told defendant that he had smelled marijuana in the boxes, gave defendant Miranda warnings, and advised him of his right to refuse consent to a search. Becker then asked for permission to search the boxes. Defendant said that he did not want the officer to search, that he wanted to leave. Becker asked Rupp to sniff the boxes, and Rupp also said that he smelled marijuana. Becker said he would detain the vehicle until he could contact the district attorney’s office to seek a search warrant, unless defendant consented to a search; the decision was up to defendant. After some discussion of the possible consequences of finding marijuana, defendant agreed to the search and signed a consent form. The officers found 37 small marijuana plants in the boxes.
The state concedes that the roadblock stop was unlawful under Nelson v. Lane County, 304 Or 97, 743 P2d 692 (1987), and State v. Boyanovsky, 304 Or 131, 743 P2d 711 (1987).1 In holding that evidence resulting from the unlawful *624stop should be suppressed, the Court of Appeals relied on Pooler v. MVD, 306 Or 47, 755 P2d 701 (1988). The state and a dissenting judge maintained that the evidence nevertheless was admissible because defendant’s consent to the search was voluntary, citing State v. Kennedy, 290 Or 493, 624 P2d 99 (1981).
The present case differs from each of these cases. At stake in Pooler was the administrative suspension of a driver’s license after an arrested driver failed a chemical breath test demanded by the arresting police officer. The governing statute applied only to tests conducted while the driver was “under arrest for driving under the influence of intoxicants,” former ORS 482.541(4), and the issue was whether the validity of the arrest was vitiated if the officer found probable cause for the arrest only when he made the unauthorized stop. This court held that the arrest was invalid because, once the evidence garnered from the unlawful stop was excluded, there was no probable cause to make the arrest on which the statute hinged suspension of the driver’s license. The present case does not involve the validity of an arrest; defendant does not claim that he was arrested before the officers found marijuana in his truck. The analogy with Pooler is that here only the unlawful stop put the officers in a position to detain defendant’s effects unless he consented to a search.
In Kennedy, two officers, acting on a call from a Florida detective, approached an airline passenger at the Portland airport. When one officer politely asked whether he might talk with the suspect, stating that he was a police officer and had information that the suspect might be carrying narcotics in his luggage, the suspect volunteered the invitation: “Would you like to search my luggage?” This court did not decide whether the encounter was a “stop” within the meaning of I *625ORS 131.605(5)2 or whether the officer had grounds for a stop, because the court concluded that in the “totality of the facts and circumstances” the defendant had voluntarily invited the officers to search his luggage.
As the Court of Appeals noted, Kennedy was based on federal Fourth Amendment precedents. Even under the “totality of circumstances” test, however, the circumstances here are unlike those in State v. Kennedy. Kennedy was not told that his suitcase would be held. He was not pressed to choose between consenting to a search of his effects or waiting while the officers sought a search warrant through the district attorney’s office.3 This case would parallel Kennedy if the officers had approached defendant’s pickup truck on a parking lot, sniffed the boxes on suspicion, asked the driver whether they might talk about their contents, and if defendant had then invited the officers to search the boxes. Of course, that is not what happened here. Unlike the officers in Kennedy, and like the officer in Pooler, these officers had no grounds to suspect defendant before the stop.4
This case again pits the “voluntariness” of a defendant’s incriminating disclosure against the judicial assessment of the acts leading to that disclosure, and it again shows that while the events and their psychic effects may be questions of fact, the legal effect of the “voluntary” disclosure remains a legal, not a factual, judgment. See State v. Wolfe, 295 Or 567, 571, 669 P2d 320 (1983); State v. Kennedy, supra, 290 Or at 502. Under the state’s view, a consent to search is voluntary if officers let a person choose to consent or to take the consequences, regardless how the officers gained the *626power to threaten the consequences and to force the choice on the person. That theory of “voluntariness” would equally apply if officers conduct a roadblock, examine all vehicles and drivers for evidence of alcohol or drugs, and then let those found with such evidence- choose either to consent to searches and chemical tests or to face warrants or license suspensions. That cannot be squared with Pooler.
We do not hold that consent can never legitimize a search when the occasion to give or refuse consent followed some unauthorized act of the police. We hold only that a search is not legitimized by consent obtained under the pressure of police action that became available to police only by the prior unauthorized conduct. Certainly officers may request permission to inspect or search one’s effects, and consent, particularly when granted after being informed of one’s right to decline, as in this case, could be a voluntary waiver of a known right. But this defendant told the officers that he did not want them to search the truck or its contents; he wanted to leave. It was only after that wish was denied that defendant began to weigh the consequences of consent against the alternative that the truck would be detained indefinitely while the officers sought a search warrant. In putting the choice to defendant in those terms, the officers (as stated in more detail in Justice Carson’s concurring opinion) were trading on evidence that they had only by virtue of the unlawful roadblock. That is a far cry from Kennedy.
The decision of the Court of Appeals is affirmed. The judgment of the circuit court is reversed, and the case is remanded to that court.
Those cases involved sobriety checkpoints clearly aimed at criminal law enforcement. We need not decide whether the license and registration checks in the present case might be sustained on less than probable cause as inspections limited to administrative sanctions, had they been designed as such; evidence of an offense unrelated to *624the reason for the inspection, if discovered without a further search, then might have been admissible in criminal as well as in administrative proceedings. See Nelson v. Lane County, 304 Or 97, 104-06, 743 P2d 692 (1987); State v. Boyanovsky, 304 Or 131, 134-35, 743 P2d 711 (1987) (Gillette, J., concurring); cf. State v. Pidcock, 306 Or 335, 759 P2d 1092 (1988). But the state does not assert that this roadblock was a regulatory I rather than a criminal law enforcement checkpoint. The officers’ good faith belief that | the checkpoint stop was lawful does not bear on the decision.
ORS 131.605(5) provides:
“As used in ORS 131.605 to 131.625, unless the context requires otherwise: «** + **
“(5) A ‘stop’ is a temporary restraint of a person’s liberty by a peace officer lawfully present in any place.”
The delay could be substantially reduced by a system making use of available technology. See State v. Brown, 301 Or 268, 278 n 6, 721 P2d 1357 (1986).
Indeed, the stop as such gave no grounds for suspicion until one officer went beyond the documents check that was its object and stepped back to lean over the bed of the truck and sniff the boxes. This differs from a police dog’s apparently random discovery of the smell of marijuana emanating from one of many storage lockers, in a place where officers were entitled to be, which supported a search on probable cause in State v. Slowikowski, 307 Or 19, 761 P2d 1315 (1988).