After stopping defendant’s automobile for a faulty headlight, a deputy sheriff arrested defendant for driving under the influence of intoxicants. When defendant was handcuffed, another officer took from defendant’s clothing a small, closed, transparent amber pill bottle which contained a white powder. The officer kept the bottle in his possession and later had the contents tested. The powder proved to be cocaine, and defendant subsequently was convicted of unlawful possession of a controlled substance, ORS 475.992, over his objections to the warrantless seizure and search that gave rise to the charge. The Court of Appeals affirmed, 59 Or App 338, 650 P2d 1062 (1982). Judge Buttler dissented on the ground that the court had misapplied the law as stated in State v. Elkins, 245 Or 279, 422 P2d 250 (1966). We allowed review to consider that question and because the Court of Appeals did not have available our later decision in State v. Caraher, 293 Or 741, 653 P2d 942 (1982). We conclude that Elkins and Caraher require reversal of this conviction.
I.
Two contemporary facts together give rise to a large proportion of legal challenges to the manner in which an officer seizes evidence resulting in a prosecution. One fact is the nearly universal use of personal automobiles. The other is the less universal but widespread consumption of drugs and other substances in pursuit of pleasure or other self-induced moods or sensations. Each has been subjected to more or less strict regulation in the interests of health and safety. The state requires vehicles to be registered and to have certain equipment in working order, and it requires drivers to qualify for and to retain drivers’ licenses, to drive only in a sober condition, and to comply with the traffic laws. The state also prohibits the possession of various regulated drugs, or “controlled substances,” for recreational or other nonmedical consumption, a prohibition that lawmakers have chosen to enforce by the penalties and procedures of criminal law. ORS 475.992. That choice may deter many potential drug users from engaging in criminal conduct; it also entitles the many others who remain undeterred to all the legal guarantees of those procedures.
*340Especially the rules governing searches and seizures are bound to come under disproportionately frequent stress when the drug laws intersect with the day-to-day enforcement of the traffic laws. Ordinarily a person walking the public streets gives officers no occasion to search his or her clothing or other effects for forbidden drugs or other contraband, unless there is probable cause or at least reasonable grounds to suspect that the person has committed a crime. ORS 131.615; State v. Fairley, 282 Or 689, 580 P2d 179 (1978); see also Kolender v. Lawson, 461 US 352, 103 S Ct 1855, 75 L Ed 2d 903 (1983). Even rarer are occasions for a valid warrantless entry followed by a patdown or search when a person is in his home or other private quarters. See State v. Davis, 295 Or 227, 666 P2d 802 (1983). These are extraordinary occasions, as the 18th century drafters of the search and seizure clauses, anticipating neither automobiles nor large, permanent police forces engaged in routine law enforcement, doubtless expected them to remain.
In the context of the traffic laws, however, almost every adult daily faces occasions to confront an officer in the course of entirely proper law enforcement activity. Officers stop vehicles because they observe defective equipment, or outdated license plates, or erratic and unsafe driving, or a large variety of minor traffic violations such as failure to stop at a stop sign, or to signal, or an improper change of lanes. A demand to see the driver’s license and the vehicle registration, also authorized by law, ORS 482.040(2)(b), prolongs the stop and may lead to further investigation. So may objects observed in plain view in the vehicle, as happened, for instance, in State v. Quinn, 290 Or 383, 623 P2d 630 (1981); State v. Downes, 285 Or 369, 591 P2d 1352 (1979); State v. Jackson, 62 Or App 7, 660 P2d 183, rev allowed 295 Or 31 (1983); State v. Tremaine, 56 Or App 271, 641 P2d 637 (1982); and State v. Alpert, 52 Or App 815, 629 P2d 878 (1981). See also Texas v. Brown, 460 US 730, 103 S Ct 1535, 75 L Ed 2d 502 (1983). The driver may appear intoxicated, and the officer may want to investigate that possibility. Often one step leads to another, and the driver or a passenger is frisked and suspect articles are seized. The present case — which began with a stop of an automobile for a defective headlight, followed by discovery of the driver’s apparent intoxication, an arrest, seizure of a small pill bottle from his pocket, and the warrantless opening of the bottle and *341test of its contents — is typical. Sometimes the steps occur in a different sequence, invalidating the logic of the chain. See State v. Carter/Dawson, 287 Or 479, 600 P2d 873 (1979).
It hardly needs demonstration that automobiles uniquely are where most persons confront routine law enforcement activity that may lead to a search and eventual prosecution for an unrelated possessory offense. About two million persons hold Oregon drivers’ licenses and about 2.5 million motor vehicles are registered in Oregon. Many others licensed or registered elsewhere travel Oregon roads. In 1981, accidents or traffic violations involving more than 370,000 drivers came to the attention of the state Motor Vehicles Division and presumably of police officers. Of these, 313,585 violations led to convictions.1 The 1982 Report of Criminal Offenses and Arrests prepared by the Law Enforcement Data System reports nearly 27,000 arrests for driving under the influence of intoxicants in 1982 alone, nearly 30 percent of all arrests of adults. Arrests for other serious traffic offenses would add many more. All potentially expose drivers to the typical pat-down and “securing” of personal effects when a person is taken into custody.
Similarly, unlawful possession of controlled substances is hardly a rare form of behavior in Oregon. Even the fraction of instances that come to police attention and actually lead to arrests produced 7,802 arrests classified as “drug abuse” in 1982. While the published statistics do not report how many prosecutions for possession of controlled substances result from stops of vehicles for other reasons, the appellate reports make clear that it is a large number. Since the establishment of the Court of Appeals in 1970, about 320 of its published opinions have dealt with challenges to the police seizure of controlled substances, nearly 200 involving vehicles. Of these, about 50 have arisen from stops of vehicles in the course of traffic law enforcement.2
*342These are not exact figures, and of course they are only a fraction of all such cases. They do not include those in which there was no prosecution, or a plea of guilty, or no appeal, or an affirmance without opinion. Most important, no statistics tell us the number of instances in which motorists stopped under traffic regulations are subjected to more or less intrusive searches in which no controlled substance or other evidence of crime is found.
Nonetheless, these numbers illustrate the extent to which the law of search and seizure today, as in the Prohibition era of the 1920s, is tested by the twin phenomena of the automobile and the socially widespread determination to disregard laws against various intoxicants, stimulants, or other drugs. As the intensive regulation of motor vehicles and their use on public streets lead to a large proportion of all stops and arrests, these common events raise persistent issues of the scope of further acts accompanying the traffic stop.3 The answers, of course, concern the rights of every ordinary motorist, not peculiarly those who are suspected of carrying a controlled substance. One such issue is the relation between legitimate warrantless police action on probable cause to enforce one law, such as a traffic regulation, and the warrant requirement when *343the initial action leads to probable cause for a search or seizure for an unrelated offense.
II.
Recent Oregon decisions have addressed this issue on both statutory and constitutional grounds. State v. Caraher, supra, reaffirmed the responsibility of Oregon courts to enforce Oregon law, including this state’s rules against conviction on illegally seized evidence, before turning to claims under the federal constitution. 293 Or at 752. The evolution of those rules is reviewed in more detail in State v. Davis, supra, 295 Or at 231-37. As this court has repeatedly stated, the proper sequence begins with an examination of ordinary rules of law and the scope and limits of legal authorization before reaching any constitutional issue, because when some challenged practice is not authorized by law, the court acts prematurely if it decides whether the practice could be authorized without violating the constitution.4
Specifically with respect to investigations incident to traffic stops, this court’s opinion in State v. Carter/Dawson, supra, quoted what the Court of Appeals wrote in that case, “based upon its analysis of both statutory and constitutional law”:
«* * * Traffic stops should be the minimum possible intrusion on Oregon motorists, and not an excuse to begin questioning, searching or investigating that is unrelated to the traffic reason for the stop.
“Simply stated, when the ‘records check’ came back ‘clear,’ Officer Miller could do no more than write a citation and send *344defendants on their way. He could not begin questioning or an investigation that had nothing to do with the objective reason for the stop (speeding). If he did so, the officer extended the duration of the stop without legally sufficient articulated cause.”
34 Or App at 32-33, 578 P2d at 796-97, quoted in 287 Or at 486. The Court of Appeals referred to the legislative policies found in ORS 131.615(2) and (3) and ORS 484.435 to limit the scope of investigatory activity incident to stops for traffic offenses.5 Even when the statutes themselves do not apply because the stop becomes an arrest, this legislative concern does not lose all significance. In the present case, however, defendant has raised no issue whether the deputy, who described himself as a “traffic officer,” was authorized to seize and retain property that is not obviously contraband from a person arrested on a traffic offense, challenging only the constitutional validity of the seizure and subsequent search of the bottle.6
*345With respect to the constitutional challenge, also, our decisions have recognized a comparable limit to the extent of searches of persons and effects without a warrant. State v. Caraher, supra, reviewed the evolution of the limits that Or Const art I, § 9, places on the scope of warrantless searches and seizures incident to an otherwise valid arrest.7 It restated the rule that in order to extend beyond the immediate necessity to protect the arresting officer or to prevent escape or the destruction of evidence, such a search or seizure of “effects” incident to an arrest must relate to the offense which prompts the arrest, citing State v. O’Neal, 251 Or 163, 444 P2d 951 (1968); State v. Krogness, 238 Or 135, 144, 388 P2d 120 (1963), cert den 377 US 992, 84 S Ct 1919, 12 L Ed 2d 1045 (1964); and State v. Chinn, 231 Or 259, 373 P2d 392 (1962). 293 Or at 759. Testing is a form of search. The state does not contend in this case that the arresting officer seized the brown pill container on any suspicion that its contents related to the apparent intoxication that led to defendant’s arrest.
In the course of a valid traffic stop of a vehicle or a permissible frisk incident to a stop or an arrest, officers sometimes may come upon other suspicious items. But these may not be seized on suspicion alone; probable cause is required. State v. Elkins, supra, found a constitutional violation in the seizure of pills in a pill bottle incident to an arrest for public drunkenness, because mere suspicion did not constitute probable cause for the officer to believe “that the article he has *346discovered is contraband and therefore a crime is being committed.” 245 Or at 284. The state’s brief in the present case proceeded on the premise that State v. Elkins had been overruled by State v. Florance, 270 Or 169, 527 P2d 1202 (1974), an assumption that the Court of Appeals properly rejected.8 The majority of that court nevertheless sustained the officer’s action in retaining and opening the bottle and testing its contents, on the theory that the characteristics of the bottle could cause a “hypothetical reasonable officer” or “an officer trained with respect to illegal drugs” reasonably to believe that the bottle contained contraband. 59 Or App at 344.
We need not follow the Court of Appeals into judicial speculations on the extent to which contemporary culture has made pill bottles and containers of white powdery substances prima facie evidence of criminal possession of their contents and therefore subject to seizure. That question is of potential concern to people who carry a supply of baby powder, or table salt, or legitimate medicines, because if observation of such a substance in an unconventional container suffices as probable cause to suspect possession of contraband, it also suffices as probable cause to arrest the person in whose possession the container is observed. In the present case, however, the seizure of the bottle incident to a valid arrest and the subsequent testing of its contents are properly analyzed not as one but as two events. For “probable cause” is not alone dispositive of both steps. The question is not simply whether probable cause to investigate, that is to say, to “search,” the contents of the bottle did or did not exist, but whether there was any need to do so without a warrant.
The constitutional text itself ties the phrase “probable cause” to warrants. It seems never to become superfluous to repeat that the requirement of a judicial warrant for a search or seizure is the rule and that authority to act on an officer’s own assessment of probable cause without a warrant is justified only by one or another exception. State v. Hansen, 295 Or 78, 664 P2d 1095 (1983); State v. Carsey, 295 Or 32, 38, 664 P2d 1085 (1983); State v. Greene, 285 Or 337, 340-41, 591 P2d 1362 (1979); State v. Miller, 269 Or 328, 334, 524 P2d 1399 (1974). The time to make the judicial determination whether there is *347probable cause for a search or a seizure, if time permits, is before the individual’s privacy is invaded. A later adjudication upon a motion to suppress evidence, although necessary, does not undo the invasion, does not help persons who are cleared and never prosecuted, and colors the perception of “probable cause” by what the search in fact revealed. See State v. Greene, supra, 285 Or at 351-355 (concurring opinion). The reasons for the exceptions from the rule are always one form or another of practical necessity to act before a warrant can be obtained.
In this case there is substantial dispute whether the officer himself reasonably believed the pill bottle to contain a controlled substance. When an officer in fact has reasonable cause for such a belief, he often will also face the practical need to retain the bottle or other container long enough for a magistrate to decide whether there is probable cause to seize and to test the unknown contents, unless the owner consents to an immediate test in order to recover his property. The exception from the warrant requirement extends to depriving the owner of possession as long as necessary to safeguard it and to obtain a speedy judicial decision. But unless the substance is volatile the practical need to proceed without a warrant normally extends no further.
Here the pill bottle was seized in the course of arresting defendant for a crime with which the bottle had nothing to do. This is the decisive distinction between this case and Caraher, which sustained the warrantless seizure of evidence from Caraher’s purse because “the arrest was for possession of a controlled substance [and] it was reasonable to believe that defendant would carry contraband in her purse.” 293 Or at 759. The present defendant was not arrested for or suspected of having any controlled substance. Nor did the indisputable nature of the substance become evident to the officers’ observation simply in the course of the routine of the arrest, as may happen when unlawful weapons, burglar tools, specific property already known to be stolen, marijuana, or other contraband is discovered in plain view in a traffic stop or a frisk.
An arrest itself is only a temporary deprivation of a person’s normal freedom to go where and when he pleases, justified by probable cause to hold the person to answer to a criminal charge or by some other legal reason. The process of arrest and the subsequent custody have incidental consequences that *348are implicitly authorized insofar as they are necessary to those functions and not needlessly “rigorous.”9 But the mere arrest and custody, divorced from the reasons for the arrest, do not subject a person and his belongings to unlimited inquisitorial powers that would not apply if he were not arrested. Both the majority and the dissent in the Court of Appeals quoted from this court’s opinion in State v. Elkins, limiting the scope of warrantless searches incident to arrests:
“ ‘If the rule were otherwise, an officer who desired to inculpate an arrested person in another crime, could seize everything in such person’s immediate possession and control upon the prospect that on further investigation some of it might prove to have been stolen or to be contraband. It would open the door to complete temporary confiscation of all an arrested person’s property which was in his immediate possession and control at the time of his arrest for the purpose of a minute examination of it in an effort to connect him with another crime. Such a practice would be as much an exploratory seizure as one made upon an arrest for which no probable cause existed. Intolerable invasions of a person’s property rights would be invited by an ex post facto authorization of a seizure made on groundless suspicion.’ 245 Or at 287-88.”
59 Or App at 341, 347.
Though the issue here is slightly different, the concern remains the same. If a search incident to an arrest is not to justify an “exploratory seizure” of “everything in such person’s immediate possession and control,” such seizures must be limited to items that reasonably relate to the probable cause for the arrest, as held in State v. Caraher, supra, and its predecessors. Other “effects” unrelated to the reason for the arrest may be seized if their nature as contraband is evident on sight or, if this determination requires tests of an unknown substance or opening of a closed container, to secure them for the least amount of time needed to obtain a warrant for this purpose upon a showing of probable cause that further search is justified. Because that was not done in this case, the search of the pill bottle and testing of its contents went beyond what is permissible without a warrant, and the motion to suppress should have been allowed.
*349A word should be added in response to the concurring opinion. Its criticism is directed chiefly against this court’s decision last year in State v. Caraher, supra. The present decision merely follows Caraher; the concurring opinion disagrees with Caraher and prefers tying Oregon to the federal rule of United States v. Robinson, 414 US 218, 94 S Ct 467, 38 L Ed 2d 427 (1973).
The court’s opinion in Caraher speaks for itself and need not be repeated here. Nor is there any reason why the Caraher rule, which we follow here, should cause the widespread confusion feared by our concurring colleagues.10 In fact, Caraher did not originate a new rule but reasserted a rule stated in three earlier Oregon decisions cited in the opinion, decisions that “expanded the justification for a search incident to arrest beyond considerations of the officer’s safety and destruction of evidence” to permit a reasonable search “when it is relevant to the crime for which defendant is being arrested.” State v. Caraher, supra, 293 Or at 759. This may not be the only or the best possible rule, see 293 Or at 770 (Lent, C. J., dissenting), but we decline the proposal of the concurring opinion to overrule these decisions.
Reversed and remanded.
Oregon Drivers 1981, Motor Vehicles Division, Oregon Department of Transportation at 36-37.
A check of 138 search and seizure decisions found in this court’s reports shows that well over half involved seizure of contraband, predominantly alcohol or drugs. Before 1935, 14 of 25 cases involved liquor or stills. Between the end of Prohibition and the beginning of the current era of drug offenses, there were only ten search and seizure cases in 27 years. Since 1962, 47 of 103 decisions have involved drugs, increasing from about 30 percent of the search and seizure cases in the 1962-1972 decade to 60 percent during the years from 1973 to 1983.
Judge Tanzer, joined by Judge Roberts, made these observations in State v. Carter/Dawson, 34 Or App 21, 578 P2d 790 (1978), modified on other grounds 287 Or 479, 600 P2d 873 (1979):
“The mere existence of a 2-miles-per-hour violation of a speed limit, a burned out tail light, an unsignalled turn, standing off the curb before the walk signal turns on, or a meander over the bounds of a crosswalk, let alone loitering, disrespect to an officer or disorderly conduct, should not serve to make reasonable a search or seizure which would be unreasonable in the absence of a commonplace and often inadvertent law violation.
“Typically [a traffic stop] . . . means making an otherwise unavailable vantage point for plain viewobservation. It is the marijuana seeds on the rear seat, the roach in the ashtray, the ski mask on the floorboard, that rob the majority doctrine of its intended surgical quality. Furthermore, the stop is the setting for observation of the bulge-in-the-jacket (which may look like a weapon but is almost invariably drugs) and the furtive gesture (all gestures beyond absolute immobility turn out to be furtive in a stop situation) which leads to stops and frisks which generally relate to the underlying suspicion rather than the pretext stop.”
34 Or App at 40, 44 (dissenting opinion). The “pretext” issue there discussed is not involved in this case.
See, e.g., Haynes v. Burks, 290 Or 75, 83, 619 P2d 632 (1980) (speedy trial statutes apply in advance of constitutional issue); State v. Tourtilott, 289 Or 845, 849 n. 4, 618 P2d 423 (1980) cert den 451 US 972, 101 S Ct 2051, 68 L Ed 2d 352 (1981) (authority to stop antecedent to constitutional issue); State v. Haynes, 288 Or 59, 70-71, 602 P2d 272 (1979), cert den 446 US 945 (1980) (no police authority to prevent counsel’s access to arrested persons); State v. Carter/Dawson, 287 Or 479, 600 P2d 873 (1979) (officer authorized to stop vehicle for actual traffic violation though motivated by suspicion of other crime); State v. Spada, 286 Or 305, 594 P2d 815 (1979) (access to evidence under public records act forecloses 14th amendment claim); State v. Heintz, 286 Or 239, 257-258, 594 P2d 385 (1979) (concurring opinion) (blood test); State v. Classen, 285 Or 221, 226, 590 P2d 1198 (1979) (exclusion of unreliable evidence); State v. Jones, 279 Or 55, 59-60, 566 P2d 867 (1977) (improperly obtained court order); State v. Valdez, 277 Or 621, 561 P2d 1006 (1977) (statutory authority to stop and frisk limited to suspicion of crime already committed).
The Court of Appeals quoted ORS 131.615, as follows:
tt * * * *
“(2) The detention and inquiry shall be conducted in the vicinity of the stop and for no longer than a reasonable time.
“(3) The inquiry shall be considered reasonable only if limited to the immediate circumstances that aroused the officer’s suspicion.’ ”
ORS 484.435 as quoted by the Court of Appeals:
“ ‘(1) Searches and seizures otherwise authorized by law incidental to an arrest shall not be authorized if the arrest is on a charge of committing a Class B, C or D traffic infraction unless the arrest is a full custody arrest in which the person arrested is to be lodged in jail, and the decision to place the person arrested under full custody arrest is based upon specific articulable facts justifying his being lodged in jail rather than being given a traffic citation as provided in this chapter and released.
“ ‘(2) Nothing in subsection (1) of this section shall be construed to forbid a frisk for' dangerous or deadly weapons authorized under ORS 131.605 to 131.625.’ ”
34 Or App at 31-32.
The question of authority cannot adequately be briefed by citing caselaw, because appellate opinions generally deal only with constitutional limitations; yet employment as an officer does not necessarily carry with it open-ended authorization to take any and all actions provided only that they are not unconstitutional. See, e.g., State v. Fairley, 282 Or 689, 580 P2d 179 (1978); Colonnade Catering v. United States, 397 US 72, 90 S Ct 774, 25 L Ed 2d 60 (1970).
For example, the State Police Manual states:
“Upon making an arrest for any offenses, members shall immediately search the person arrested for concealed weapons to avoid the possibility of assault or escape and for any incriminating evidence.”
*345Department of State Police, Manual, Art. XI, § 19 (1979). We understand this section to direct the officer to search for “incriminating evidence” of the offense for which he is “making an arrest,” consistent with State v. Caraher, supra, not for all items that might possibly be incriminating in relation to an offense not otherwise known to the officer. Also indicative is section 22 of the manual, which recognizes “stop and frisk” as a “severe restriction on individual rights” and limits its use to reasonable suspicion of felonies or misdemeanors for which a sentence “in prison” is authorized, accordingly excluding violations.
The arrest in this case was not made by state police officers.
Or Const art I, § 9:
“No law shall violate the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable search, or seizure; and no warrant shall issue but upon probable cause, supported by oath, or affirmation, and particularly describing the place to be searched, and the person or thing to be seized.”
The state also cites State v. Brown, 291 Or 642, 634 P2d 212 (1981), but that case was presented and decided solely under federal fourth amendment caselaw.
Or Const art I, § 13:
“No person arrested, or confined in jail, shall be treated with unnecessary rigor.”
We do not think it proper in this opinion to comment on the accuracy of the parade of examples in the concurring opinion’s “Pandora’s box.” The concurring opinion is correct that the Court of Appeals shares initial responsibility for deciding issues of Oregon law without awaiting decisions of this court.