The defendants in these cases were arrested at roadblocks set up by the Concord Police Department to detect and apprehend drunk drivers. Each was charged with driving while under the influence of intoxicating liquor (DWI). RSA 265:82 (Supp. 1983). In advance of trial, both moved to suppress certain items of evidence, arguing that the use of the roadblocks by the police violated their rights under the State and Federal Constitutions. The motions were consolidated for hearing, after which the District Court (Robbins, J.) denied both motions. Upon request of the defendants, the issue of the roadblocks’ constitutionality was transferred to this court, pursuant to RSA 502-A:17-a. The following questions of law were transferred:
“A. Whether police conduct using roadblocks specifically established for the purpose of determining whether the driver of a motor vehicle is driving under the influence of an intoxicating liquor in violation of New Hampshire RSA 265:82, violates a defendant’s constitutional guarantees against unreasonable searches and seizures as provided by part 1, article 19 of the New Hampshire Constitution and the fourth amendment to the United States Constitution?
“B. Whether the New Hampshire Supreme Court’s ruling in the case of State v. Severance, 108 N.H. 404 (1968), in which it was stated that a roadblock ‘for the good faith purpose of inspecting motor vehicle licenses and registration certificates is a valid method of enforcing public safety so long as the roadcheck is not used as a subterfuge for uncovering evidence of other crimes,’ prohibits roadblocks specifically established for the purpose of determining whether the driver of a motor vehicle is driving while *288under the influence of intoxicating liquor in violation of New Hampshire RSA 265:82?”
For the reasons that follow, we hold that the roadblocks in these cases failed to meet constitutional standards, and we reverse the trial court’s denial of the motions to suppress.
The Concord Police Department inplemented a program of drunk driving roadblocks in April 1984. The basis for the program was a document, drafted by a planning and research officer in the department, describing a “Standard Operating Procedure” (SOP).
The SOP stressed several points: that the roadblock should involve “minimal intrusion”; that its location should be determined “by an official based upon objective data (i.e., the number of accidents, injury accidents and/or DWI arrests)”; that “the decision as to which vehicles will be stopped (e.g., all east-bound vehicles, or every 10th vehicle) cannot be left to the discretion of the officers at the scene but must be made in advance”; and that “the checkpoint must be clearly indicated and manned by uniformed officers.” It is conceded by the State in its brief that “[t]he purpose of the roadblocks is to detect operators who may be driving under the influence of alcoholic beverages....”
The record indicates that 47 roadblocks were set up on 21 weekr end nights between April 29, 1984, and October 20, 1984. A total of 1,680 vehicles were stopped, resulting in only 18 DWI arrests. During roughly the same six months, the Concord police made 175 DWI arrests by traditional methods; i.e., through the use of roving patrols.
The defendant Koppel was arrested on July 7, 1984, at 1:00 a.m., at a roadblock on Loudon Road near the Everett Arena. The defendant Forest was arrested on August 5, 1984, at approximately 1:35 a.m., at a roadblock on East Side Drive, at the end of an exit ramp from Interstate Route 393.
Both roadblocks consisted of three or more marked police cars parked at or near the side of the road with their lights on, accompanied by several officers wearing reflectorized clothing. In at least one case, the officer primarily responsible for stopping traffic was illuminated with a spotlight.
When traffic was light, every car approaching the roadblock was stopped. If five cars were detained at the roadblock, other traffic was waved on until a car left the roadblock, at which time the next car to approach would be detained.
There were no signs warning drivers of either roadblock, nor any advance publicity of their occurrence. A driver stopped at either roadblock had no way of learning its purpose except from the offi*289cers manning the roadblock. In the case of the Loudon Road roadblock, it would have been impossible for a driver approaching the roadblock to avoid it, because the road is a divided highway at that point.
The defendants have challenged the validity of the roadblocks under both part I, article 19 of the New Hampshire Constitution and the fourth amendment of the United States Constitution. We begin, as we must, by first making an independent analysis of the protections afforded under the New Hampshire Constitution, State v. Ball, 124 N.H. 226, 231, 471 A.2d 347, 350 (1983), using decisions of the United States Supreme Court and other jurisdictions only as aids in our analysis, see Michigan v. Long, 103 S. Ct. 3469, 3476 (1983). Thereafter, we need address federal constitutional issues only insofar as federal law would provide greater protection. State v. Ball, 124 N.H. at 232, 471 A.2d at 351.
Part I, article 19 gives every citizen of the State “a right to be secure from all unreasonable searches and seizures of his person, his houses, his papers, and all his possessions.” Although this language is similar to that in the Federal Constitution, this court has held that article 19 provides greater protection for individual rights than does the fourth amendment. State v. Ball, supra at 235, 471 A.2d at 353; State v. Sidebotham, 124 N.H. 682, 686-87, 474 A.2d 1377, 1379-80 (1984).
It is commonly recognized that the stopping of a motor vehicle is not a mere “encounter” as described in Terry v. Ohio, 392 U.S. 1, 13-14 (1968), but is a more intrusive seizure subject to greater constitutional limitations. See People v. John BB., 56 N.Y.2d 482, 487, 438 N.E.2d 864, 866, 453 N.Y.S.2d 158, 161, cert. denied, 459 U.S. 1010 (1982); cf Berkemer v. McCarty, 104 S. Ct. 3138, 3150 (1984). Stopping and detaining an automobile and its occupants, whether by roving patrol or roving roadblock, constitutes a seizure within the meaning of article 19 of our State Constitution. See State v. Landry, 116 N.H. 288, 289, 358 A.2d 661, 663 (1976) (construing fourth amendment). In State v. Ball, we reiterated that “we interpret part I, article 19 to reflect the intent of the framers that all searches and seizures must be reasonable. Unless a warrantless search [or seizure] falls within one of the few specifically established and well-delineated exceptions, it is per se unreasonble.” Ball, supra at 234, 471 A.2d at 362.
The State argues that an exception to the warrant requirement exists in this case, and points to a test that we have previously applied in fourth amendment cases. In State v. Landry, we held that
*290“the reasonableness of such a seizure [of an automobile] depends on the balance between the public interest in law enforcement and the individual’s right to personal security free from aribtrary action by law officers. More specifically in a case like this one [involving the stop of a single vehicle by a roving patrol] the competing considerations are the State’s compelling interest in maintaining safety on the public highways and the motorist’s reasonable expectation of privacy when he is traveling on these highways in his automobile.”
Landry, 116 N.H. at 289-90, 358 A.2d at 663. See also State v. Baldwin, 124 N.H. 770, 774, 475 A.2d 522, 524 (1984).
We had earlier applied a similar test in State v. Severance, 108 N.H. 404, 237 A.2d 683 (1968). Severance involved a police roadblock, the alleged purpose of which was to check for proper licenses and registrations. We held that a roadblock used for such purposes was “a constitutionally valid method of enforcing public safety so long as the road check is not used as a subterfuge for uncovering evidence of other crimes.” Id. at 408, 237 A.2d at 686.
Our holding in Severance was based on the demonstrable fact that road checks were the only effective means available to law enforcement authorities of enforcing the license and registration laws. Id. at 407, 237 A.2d at 685 (citing Commonwealth v. Mitchell, 355 S.W.2d 686, 688-89 (Ky. 1962)). However, in Delaware v. Prouse, 440 U.S. 648 (1979), the United States Supreme Court held that the fourth amendment requires strict limits on the type of road check that can be used even for so limited a purpose.
Applying a test similar to the one we used in Landry and Severance, see Prouse, 440 U.S. at 854, the Court held that “spot checks,” carried out at the discretion of individual police officers, were an impermissible means of enforcing license and registration laws.
The Court agreed “that the States have a vital interest in ensuring that only those qualified to do so are permitted to operate motor vehicles, that these vehicles are fit for safe operation, and hence that licensing, registration, and vehicle inspection requirements are being observed.” Id. at 658. The Court, however, went on to say:
“It seems common sense that the percentage of all drivers on the road who are driving without a license is very small and that the number of licensed drivers who will be stopped in order to find one unlicensed operator will be large indeed. The contribution to highway safety made by discretionary stops selected from among drivers generally will therefore be marginal at best.”
*291Id. at 659-50.
The Court concluded that this “marginal contribution to roadway safety . . . cannot justify subjecting every occupant of every vehicle on the roads to a seizure ... at the unbridled discretion of law enforcement officials.” Id. at 661. It noted, however, that
“[t]his holding does not preclude . . . States from developing methods for spot checks that involve less intrusion or that do not involve the unconstrained exercise of discretion. Questioning of all oncoming traffic at roadblock-type stops is one possible alternative.”
Id. at 663.
The Court’s dictum in Prouse has been cited frequently as authority for upholding the constitutionality of drunk-driving roadblocks. E.g., State v. Super. Ct. in & for County of Pima, 691 P.2d 1073, 1076-77 (Ariz. 1984); Little v. State, 300 Md. 485, 498, 479 A.2d 903, 909 (1984); State v. Deskins, 234 Kan. 529, 540-42, 673 P.2d 1174, 1179 (1983). At the outset, however, we note two major features of this case that distinguish it from the Prouse dictum: (1) the defendants here have invoked the protection, not merely of the fourth amendment, but also of part I, article 19 of the State Constitution; and (2), unlike the spot checks in Prouse, the roadblocks here in question were conducted to discover evidence to be used in the prosecution of serious criminal offenses.
Our construction of article 19 has, as noted above, varied significantly from fourth amendment doctrine. In State v. Ball, we held that seizure of a hand-rolled cigarette from an automobile, based on mere suspicion that it contained contraband, was unconstitutional. Ball, 124 N.H. at 237, 471 A.2d at 354 (departing from fourth amendment analysis in Texas v. Brown, 460 U.S. 730 (1983)).
Similarly, in State v. Sideboiham, a majority of the court held that “a defendant . . . charged . . . with an offense arising out of his possession of a motor vehicle, must be afforded ‘automatic standing’ ... to challenge the legality of any search of that motor vehicle ....” Sidebotham, 124 N.H. at 687, 474 A.2d at 1379-80 (rejecting “expectation of privacy” rule of United States v. Salvucci, 448 U.S. 83 (1980)).
These cases and others have established that, where the search or seizure of a motor vehicle is involved, article 19 provides significantly greater protection than the fourth amendment against intrusion by the State. Accordingly, in evaluating the constitutionality of a warrantless search or seizure, we will apply a more stringent test in cases like this one than we applied in Landry. To justify *292the search or seizure of a motor vehicle, absent probable cause or even a reasonable suspicion that a criminal offense is being committed, the State must prove that its conduct significantly advances the public interest in a manner that outweighs the accompanying intrusion on individual rights. It must further prove that no less intrusive means are available to accomplish the State’s goal.
Such a test was implicit in Severance, where we noted, as mentioned above, that road checks were the only practical means of detecting unlicensed drivers and unregistered cars. Here, the admitted purpose of the roadblocks in the instant case becomes crucial. As the Appellate Court of Illinois has said:
“[I]n cases where the Supreme Court has either expressly or impliedly sanctioned checkpoint stops, the criminal activity targeted was of such a nature that there was no other less intrusive but equally effective means of detecting violators. Transporters of illegal aliens and violators of license and safety equipment laws can rarely be detected by observing traffic.
“In contrast, the foremost method of detecting drunk drivers has been by observing driving behavior.”
People v. Bartley, 466 N.E.2d 346, 348 (Ill. App. Ct. 1984) (citing Prouse and United States v. Martinez-Fuerte, 428 U.S. 543 (1976)); see also State v. Smith, 674 P.2d 562, 565 (Okla. Crim. App. 1984).
We agree that the State’s interest in detecting drunk drivers is great. See South Dakota v. Neville, 459 U.S. 553, 558-59 (1983). The validity of these roadblocks, however, depends first, on whether they are more effective toward advancing this interest than other, less intrusive means; and second, on whether their value outweighs the degree of intrusion they involve. :/?,
The statistics cited earlier for the Concord roadblocks bear out the Bartley court’s view that roadblocks are not a particularly effective means of detecting drunk drivers. For each 100 vehicles “seized” and detained by the police for a period of one to five minutes, only one arrest for driving under the influence was made. Like the spot checks in Prouse, it appears that an inordinate number of law-abiding citizens must be stopped at roadblocks in order to make only a few arrests. The trial court could not find, on this record, that roadblocks are any more effective at detecting drunk drivers than other, substantially less intrusive, means.
In its brief, the State also alluded to the possibility that roadblocks deter drunk driving. Notwithstanding the fact that there is *293no evidence in the record regarding the potential deterrent effect of the roadblocks in this case, other courts have recognized that roadblocks may have a deterrent impact on drunk driving. Little v. State, 300 Md. at 505-06, 479 A.2d at 913; People v. Scott, 483 N.Y.S.2d 649, 652-54, 473 N.E.2d 1, 4-6 (1984).
We agree that roadblocks may have such an effect and that in determining whether such roadblocks advance the public interest so as to outweigh the accompanying intrusion on individual rights, or whether less intrusive means are available to accomplish the State’s goal, we should separately consider the deterrent effect. Accordingly, we consider whether the roadblocks in this case were so intrusive on individual rights as to exceed constitutional limits, notwithstanding their value as a deterrent. We hold that they were.
As the Scott court pointed out, it is publicity about roadblocks that is “the chief means of deterring driving while intoxicated,” People v. Scott, 483 N.Y.S.2d at 652, 473 N.E.2d at 4 (citing a 1983 paper on Safety Checkpoints For DWI Enforcement issued by the Department of Transportation’s National Highway Traffic Safety Administration’s Office of Alcohol Countermeasures). Although we have no doubt that many people learned of the Concord roadblock program after it began, its potential deterrent value was lessened, and its potential for surprise was increased, by the lack of advance publicity.
More important, there is nothing in this record, nor in decisions from other jurisdictions, to indicate that a roadblock program has any greater deterrent value than a well-publicized program of highly visible roving patrols. To justify the greater intrusiveness of roadblocks, the State would have to prove that they had a substantially greater deterrent value than such a program. This has not been done.
As to the actual degree of intrusion involved, there is dictum to the effect that a roadblock of the type used in Severance involves only “momentary inconvenience and minimal intrusion ....” State v. Baldwin, 124 N.H. at 775, 475 A.2d at 525. As we have already noted, however, Severance involved a roadblock whose purpose— checking licenses and registrations — could not be accomplished by other methods; the Baldwin court’s characterization of the roadblock should be read in that context.
The valid roadblock in Martinez-Fuerte also had a purpose-detection of smugglers and illegal aliens — for which it was the only effective means. It was also in a permanent location, and its existence and purpose were common knowledge. Martinez-Fuerte, 428 U.S. at 556, 559. Other courts have found important differences between that roadblock and a temporary, unpublicized drunk-*294driving roadblock, usually set up only at night, sometimes poorly illuminated, whose purpose becomes known only when the driver is asked for his or her license. See, e.g., People v. Bartley, 466 N.E.2d at 348; State v. Smith, 674 P.2d at 565. A roadblock of the latter type produces a substantially greater amount of “subjective intrusion— the generation of concern or even fright on the part of lawful travelers,” Martinez-Fuerte, 428 U.S. at 558, which both article 19 and the fourth amendment were intended to prevent.
We are also concerned here with a more subtle kind of intrusion. This was recognized by the Court of Criminal Appeals of Oklahoma, when it found that drunk-driving roadblocks,
“while commendable in their ultimate goal of removing [drunk-driving] offenders from the public highways, draw dangerously close to what may be referred to as a police state. Here, the state agencies have ignored the presumption of innocence, assuming that criminal conduct must be occurring on the roads and highways, and have taken an ‘end justifies the means’ approach. The Court is not so naive to think that criminal conduct does not occur regularly in the form of [drunk-driving] offenders. Yet, a basic tenet of American jurisprudence is that the government cannot assume criminal conduct in effectuating a stop such as the one presented herein. Were the authorities allowed to maintain such activities as presented in this case, the next logical step would be to allow similar stops for searching out other types of criminal offenders. For example, it is well known to the public that shoplifting is an everyday occurrence .... Are law enforcement authorities then to be allowed to establish fixed checkpoints, permanent or otherwise, outside of every shopping center in the area to question all exiting shoppers as to whether they possess sales receipts? Are law enforcement authorities to be allowed to demand all shoppers to produce such receipts or be subject to arrest everytime they go shopping? The potential for abuse is apparent.”
State v. Smith, 674 P.2d at 564-65.
Because the State has failed to show that drunk-driving roadblocks produce sufficient public benefit to outweigh their intrusion on individual rights, the case is remanded to the district court with instructions to grant the defendants’ motions to suppress. Because our holding rests solely on our interpretation of the New Hampshire Constitution, we need not discuss the scope of protection *295provided by the fourth amendment to the United States Constitution.
Reversed and remanded.
Souter, J., dissented; the others concurred.