Guidelines for Coordinating Sobriety Checkpoints

Ongoing Program to Deter Impaired Driving
Agencies considering implementing low-staffing sobriety checkpoints should integrate them with a continuing, systematic, and aggressive enforcement program. Vigorous enforcement and communication strategy need to be part of this program. The purpose of the checkpoint is to maximize the deterrent effect and increase the perception of “risk of apprehension” to motorists who operate vehicles while impaired by alcohol or other drugs.

Judicial Support
When officials decide to use low-staffing sobriety checkpoints, they should involve their prosecuting attorneys (district attorney, attorney general, etc.) in the planning process to determine legally acceptable procedures. The prosecutor can assist in identifying any legally mandated requirements and the types of evidential information needed to prosecute cases emanating from checkpoint apprehension. The jurisdiction’s presiding judge should be informed of the proposed checkpoints and procedures, an essential step if the judiciary is to accept their use. The judge can provide insight into what activities would be required to successfully adjudicate such cases. Prosecutors, judges, and other involved members of the criminal justice system can be invited to observe the actual operation of the checkpoint.

Existing Policy/Guidelines
Before using sobriety checkpoints, the agency must have specifically established procedures outlining how the checkpoints are to be conducted. The courts have been very clear in requiring the advanced planning of sobriety checkpoints. Failure to do so has been used as evidence that the checkpoint techniques involved unfettered discretion. The policy should also assure that the checkpoints are conducted with a minimal amount of intrusion or motorist inconvenience.

Site Selection
Planning should assure the safety of the general public and law enforcement officers when selecting an operational site. Sobriety checkpoints must not create more of a traffic hazard than the results of the driving behavior they are trying to modify. Planners should remember to select a site that allows officers to pull vehicles out of the traffic stream without causing significant subjective intrusion (fright) to the drivers (United States v. Ortiz 422 U.S. 891 [1975]) and/or creating a safety hazard, e.g., by creating a traffic backup. Furthermore, officers’ safety must be taken into account when deciding where to locate the checkpoint. The department should objectively outline criteria used in the site selection process, e.g., an unusual incidence of alcohol/drug involved crashes or driving violations, unusual number of nighttime single-vehicle crashes, or other documented alcohol/drug-related vehicular incidents. The site should permit the safe flow of traffic through the checkpoint. Consideration should be given to the posted speed limits, traffic volume, and visibility. Most jurisdictions have the capability to review the Average Traffic Volume (ATV) during the surveillance period for major roadways in their area.

Once a jurisdiction has decided on possible locations for the sobriety checkpoints, the effect on traffic flow can be determined by ascertaining how long each interview takes, then, multiply by the number of available officers, and finally, divide by the average number of vehicles that can be expected at that location. This will suggest whether all vehicles can be examined without causing a traffic build-up.

If the traffic volume precludes stopping every vehicle, a nondiscretionary scheme should be adopted, in advance, for stopping some subset of vehicles. In Delaware v. Prouse, 440 U.S. 648 (1979), the U. S. Supreme Court ruled that stopping all cars would be an acceptable method of conducting spot checks. In a concurring opinion, Justice Blackmun (joined by Justice Powell) added that other methods would also be acceptable, such as stopping every tenth car that passes a given point. If every vehicle is not stopped, the method used to determine which ones will must appear in the administrative order authorizing the use of the sobriety checkpoint.

The site should have maximum visibility from each direction and sufficient illumination for the safety of both the motorists and officers. If permanent lighting is unavailable, ensure that adequate portable lighting is provided. Planners should also ensure that sufficient adjoining space is available to pull vehicles off the traveled portion of the roadway. Any other conditions that may pose a hazard should be taken into consideration.

Warning Devices
Special care should be taken to warn approaching motorists of the sobriety checkpoint. Such notice can be accomplished using warning signs indicating the upcoming checkpoint, flares or fuses (if weather permits) and safety cones or similar devices for marking and/or closing lanes on the roadway, permanent or portable lighting to illuminate the checkpoint area, and marked patrol vehicles with warning lights flashing. A sign or device should be placed to provide advance warning stating why motorists are being stopped. The U.S. Supreme Court has found that visible signs of the officers’ authority generate less concern and fright on the part of lawful travelers, and is therefore less of a subjective intrusion (United States v. Martinez-Fuerte, 428 U.S. 643 [1976]). The placement and types of traffic control devices used should comply with Federal, State or local transportation codes. Planners should check with
appropriate agencies administering the location and placement of signing devices.

Visible Police Authority
The visibility of uniformed officers and their marked vehicles makes the police presence obvious. It also serves to reassure motorists of the legitimate nature of the activity. This is an important aspect of the sobriety checkpoint and part of the effort to reduce the intrusion to the passing motorists affected by the checkpoint. A sworn, uniformed officer should be assigned to provide on-site supervision of the checkpoint operation. This officer should be responsible for the overall operation and should be well versed in contingency planning for the checkpoint. The checkpoint should be staffed by a sufficient number of uniformed personnel to assure a safe and efficient operation, based on traffic volume, roadway size, type of location, etc.

Chemical Testing Logistics
Since impaired driving arrests are anticipated at the selected location, the logistics of chemical testing must also be included. If possible, a mobile breath-testing unit with a qualified operator could be physically located at the checkpoint. If one is not available, a system for expeditiously transporting suspected violators to chemical test sites should be established. In applicable locations, a drug recognition expert (DRE) should be available to examine subjects who may be impaired by drugs other than or in combination with alcohol.

Contingency Planning
Any deviation from the predetermined plan for stopping vehicles should be thoroughly documented and the reason for the deviation given (e.g., traffic backing up, intermittent inclement weather). Courts have allowed this as long as documentation of the reason requiring the deviation from the interview sequence is kept (United States v. Prichard, 645 F2d 854). If such an event occurs, jurisdictions
should have prepared an alternative plan, in advance, to
handle the checkpoint.

Detection and Investigation Techniques
An agency considering the use of sobriety checkpoints should ensure that the participating officers are properly trained in detecting impaired drivers. The use of sobriety checkpoints that allow impaired drivers to pass through undetected will not achieve the desired deterrence effect. Officers should look for the following indicators of impairment during initial contact with a driver at a checkpoint: odor of alcoholic beverages or other drugs (marijuana, hashish, some inhalants); bloodshot eyes; alcohol containers or
drug paraphernalia; fumbling fingers; slurred speech; admission of drinking or drug use; inconsistent responses; detection of alcohol by a passive alcohol sensor; etc. It is highly desirable that officers assigned to conduct the sobriety checkpoint receive the DWI Detection and Standardized Field Sobriety Testing (SFST) training. Police are using the techniques taught in the SFST course to quickly detect signs of driver impairment.

Once an officer’s suspicion is raised, further investigation can take place out of the traffic lane without impeding the flow of traffic. If an officer believes it is necessary to move a suspect’s car after reasonable suspicion of impairment, it should be moved by someone other than the suspect. The officer should then continue the investigation using nonincriminating divided-attention questions (e.g., by the officer simultaneously asking for driver’s license and vehicle registration, requiring the subject to do two things at once) and the administration of the SFST battery, which includes the Walk-and-Turn test, One-Leg Stand test, and Horizontal Gaze Nystagmus test. After the completion of the SFST, the officer may use a portable breath-testing (PBT) device, if permissible in that jurisdiction. An evidential test to determine the blood alcohol concentration (BAC) should then be administered. If the officer determines the subject is impaired and obtains a low BAC, a DRE should be used for further investigation. If a DRE is not available, normal departmental procedures regarding drug-impaired drivers should be followed.

Operational Briefings
The success of a sobriety checkpoint depends greatly upon smooth and efficient operations. The people selected as supervisors of the operation should be briefed thoroughly on all procedures. This includes maintaining as little delay to the motoring public as possible and keeping records of any deviation from the original operational plan. People selected to staffing the checkpoint should be briefed on both its purpose and operation. To avoid subjectivity, officers should understand the necessity of asking standard and uniform questions of drivers. The use of an operational briefing is essential in accomplishing this requirement.

Communication Strategy
To obtain maximum benefit in terms of its general deterrent effect, low-staffing sobriety checkpoints should be publicized aggressively. Most drivers will probably never encounter a sobriety checkpoint, but will only learn of it through media reports or by word of mouth. These two valuable forms of public communication will greatly enhance the program and should be employed consistently throughout the duration of enforcement efforts. Checkpoints are an ideal opportunity to give educational material regarding impaired driving, speeding, child restraints and seat belt usage, as well as seasonal reminders such as when schools are opening, to people stopped at the checkpoint.

Data Collection and Evaluation
A systematic method of data collection and evaluation should be used to monitor and ensure standardization and consistency of sobriety checkpoints. This may be done by measuring the reaction of the public to the checkpoint and an administrative evaluation of collected data. Listed below are some methods for evaluation.

Public Reaction
The public’s reaction can be measured by immediate feedback received by officers at the site of the sobriety checkpoint. Also, a short questionnaire, which includes an explanation of why the checkpoint is conducted, given to drivers stopped at the checkpoint can provide data. The questionnaire may ask the driver such questions as: Does the driver believe the checkpoint is fair? Did the driver mind being stopped briefly? Did the driver feel checkpoints help deter impaired driving? The responses can be completed later and mailed to the agency. If the jurisdiction has the resources, a stamped, self-addressed postcard can be used for the questionnaire.

This concerns the extent to which the program’s implementation, operation, and efficiency meets targets set for the program. The following items may be addressed:

  • number of vehicles passing through the checkpoint;
  • average time delay to motorists;
  • number of motorists detained for field sobriety testing;
  • number and types of arrests;
  • identification of unusual incidents such as safety problems or other concerns;
  • reaction of police officers participating in the sobriety checkpoint, including degree of support and effect on morale;
  • perception of the quality of checkpoint cases brought before prosecutors and judges, including special problems;
  • change in number of impaired-driving arrests;
  • change in number of impaired-driving related nighttime crashes;
  • other information deemed necessary by individual agencies.

NHTSA strongly supports the regular use of sobriety checkpoints. They should be integrated into an overall alcohol- and drug-impaired-driving program, along with vigorous selective enforcement, public information, and education. Effective enforcement of impaired-driving laws, combined with swift and sure driver’s license removal, and provides the most important elements for reducing alcohol-related fatal- and serious-injury crashes. Roadside sobriety checkpoints have provided some of the most effective results of any enforcement program. Checkpoints are an important part of a comprehensive enforcement program designed to raise the perceived probability among potential impaired drivers that they will be stopped and arrested for DWI.