DOT HS 807 656
The Use of Sobriety Checkpoints
Impaired Driving Enforcement
TRAFFIC SAFETY PROGRAMS
Office of Enforcement
Impaired driving and impaired-related crashes constitute one of the nation's leading
health problems. These events result in more deaths each year than do total
homicides. The impact is particularly severe among young people, age 15-24, where
impaired driving is the leading cause of death. Clearly, impaired driving and impaired
related crashes constitute a major threat to the safety and well-being of the public. The
costs resulting from alcohol-related crashes should be recognized and weighed against
the costs and inconveniences associated with efforts to reduce them.
These guidelines have been designed to provide law enforcement agencies with a
uniform and successful method to plan, operate and evaluate sobriety checkpoints.
When implemented in conjunction with departmental policy and any constraints
imposed by state or local courts, sobriety checkpoints provide an effective enforcement
tool to combat the impaired driving problem.
Any agency considering the use of sobriety checkpoints should integrate them with a
continuing, systematic and aggressive program, including vigorous enforcement, public
information and education. The purpose of the program is to maximize the deterrent
effect and increase the perception of "risk of apprehension" of motorists who would
operate a vehicle while impaired by alcohol or drugs. There is convincing evidence
that the use of checkpoints has a marked, dramatic effect on reducing alcohol-related
crashes in a community.1
The National Highway Traffic Safety Administration wishes to express its appreciation
to Sergeant Barbara Bent, Dayton Police Department, Dayton, Ohio; Sheriff Earl Smith,
Franklin County Sheriff's Department, Columbus, Ohio; 1st Sergeant Larry Larkin,
Indiana State Police; Maryland State Police; Lieutenant Nancy Brunzos, Sergeant
David Kochubka and Technician Floyd Wing, Metropolitan Police Department,
Washington, D.C.; 1st Lieutenant Al Slaughter, Michigan State Police; Major Raymond
Dutcher, New York State Police; Deputy Charles Fortunato, Palm Beach County
Sheriff's Department, West Palm Beach, Florida; Sergeant Keith Adams, Redding
Police Department, Redding, California. We are grateful for the effort and contribution
from each of these individuals.
We also wish to acknowledge the International Association of Chiefs of Police (IACP)
and the National Sheriffs' Association for their recommendations and participation. Mr.
Charles Peltier (IACP) provided valuable technical assistance.
1 "Sobriety Checkpoints for DWI Enforcement - A Review of Current Research,"
National Highway Traffic Safety Administration, 1987
GUIDELINES FOR SOBRIETY CHECKPOINTS
These guidelines suggest and describe operational procedures that police
administrators may want to consider in order to ensure that sobriety checkpoints are
used legally, effectively and safely. These points are consistent with those specified in
recent court decisions, including the United States Supreme Court ruling in Michigan
Department of State Police v. Sitz, upholding the constitutionality of sobriety
checkpoints. An effective sobriety checkpoint program consists of the following
Ongoing Program to Deter Impaired Driving
Existing Departmental Policy
Special Warning Devices
Visible Police Authority
Chemical Testing Logistics
Detection and Investigation Techniques
Comprehensive Public Information and Education Programs
Data Collection and Evaluation
Ongoing Program to Deter Impaired Driving - Agencies considering
implementing sobriety checkpoints should integrate them with a continuing,
systematic and aggressive enforcement program. Vigorous enforcement, public
information and education 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 would operate a vehicle while impaired by
alcohol or other drugs. The use of checkpoints alone will not maintain the
perception of risk essential to an effective general deterrence program.
Judicial Support - When officials decide to use sobriety checkpoints, they should
involve their prosecuting attorney (district attorney, attorney general, etc.) in the
planning process to determine legally acceptable procedures. This person can
assist in identifying any legally mandated requirements and the types of evidential
information that will be needed to prosecute cases emanating from checkpoint
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 on what activities would be required to successfully adjudicate
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 advance 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
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, multiplying that time by the number of available officers, and finally,
dividing that figure into the average number of vehicles which 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 United States Supreme Court indicates that
stopping all cars would be an acceptable method of conducting spot checks. In a
concurring opinion, Justice Blackmum (joined by Justice Powell) suggests 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 be stopped 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 fusees (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 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 Technician (DRT) should be available, at
a suitable location, 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 which 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 these techniques taught in the SFST
course to quickly detect whether a driver is impaired.
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 he or she has reasonable suspicion of impairment, it
should be moved by someone other than the suspect.
The officer should then continue the investigation using non- incriminating 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. After the completion of the
SFST, the officer may use a portable breath testing device (PBT), 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 DRT
should be utilized for further investigation. If a DRT 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 persons 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.
Persons selected to staff the checkpoint should be briefed on both its purpose and
operation. They should understand the necessity for standard and uniform
questions asked of drivers to avoid subjectivity. The use of an operational briefing
is one way to accomplish this.
Public Information and Education - To obtain maximum benefit in terms of its
general deterrent effect, 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 any such program and should be
Checkpoints are an ideal opportunity to give educational materials regarding
impaired driving, speeding, child restraint and seat belt usage, as well as seasonal
reminders such as schools opening, to persons 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 administrative evaluation of collected data.
Public reaction - This 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. It may ask of 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 driving while
impaired? The response can be completed later and mailed back to the agency.
If the jurisdiction has the resources, a stamped, self-addressed postcard can be
used as the questionnaire.
Evaluation - 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
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
The National Highway Traffic Safety Administration strongly supports the regular use of
sobriety checkpoints. They should be integrated into an overall drunk and drugged
driving program, along with vigorous selective enforcement, public information and
education. Effective enforcement of drunk driving laws, combined with swift and sure
license removal, provides the most important element for reducing alcohol-related fatal
and serious injury crashes. Roadside sobriety checkpoints have provided among the
most effective results of any enforcement procedure. 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
1. Has your agency used sobriety checkpoints in the past?
YES _______ NO _______
2. Is your agency currently using sobriety checkpoints?
YES _______ NO _______
3. Does your agency plan on using sobriety checkpoints in the future?
YES _______ NO _______
4. If your agency uses checkpoints, how many arrests were made at checkpoints for
impaired driving offenses? Add additional years if necessary.
NUMBER _______ YEAR _______
5. List other law enforcement agencies in your state who conduct sobriety checkpoints.
6. List any significant decline in blood alcohol levels of impaired
driving arrests or reduction in alcohol related crashes attributed to sobriety
7. Does your agency have a written policy governing sobriety checkpoints?
YES _______ NO _______
A - 1
SOBRIETY CHECKPOINTS BRIEFING GUIDE
Prior to conducting the sobriety checkpoint, the following items should be discussed
and thoroughly explained to all officers and supervisors participating in the detail.
Routine information, such as location, times, and personnel assignments, including
chemical test operators, should be included at each briefing.
Explain the goal(s) of the roadside sobriety checkpoint.
Discuss the sobriety checkpoint location and the statistical data
supporting the chosen checkpoint site.
Stress the need for safety for both the officers and motorists
Assign the sobriety checkpoint operational supervisor. The
supervisor shall remain at the checkpoint location to oversee all
on-site enforcement activities.
Discuss the placement of personnel and traffic control devices in
conformance with established roadside sobriety checkpoint
guidelines and federal, state and/or municipal signing regulations.
Develop and establish a systematic approach to stopping the
vehicles as they enter the checkpoint location. For example, all
vehicles or every fifth vehicle will be stopped. At no time will a
random stop be utilized. If a problem such as traffic congestion
occurs and requires a change in the pattern of stopping vehicles,
the on-scene supervisor will determine if there will be a change
from the systematic vehicles stopping sequence. All changes, no
matter how slight, shall be documented including the time of
change with an appropriate explanation of the reason for the
Instruct all participating officers to explain the purpose of the
checkpoint to the motorist as they approach a vehicle. A uniform
statement/question to the driver should be used, for example:
A - 2
"Good Evening. You have been stopped at a Department Name
sobriety checkpoint. We use checkpoints in an effort to detect and
deter the impaired driver. Have you consumed any alcohol or
controlled substance today?"
If the driver's answer is no and there is no other compelling reason
to detain the vehicle, the officer should permit the motorist to
If the driver's answer is yes, ask how much and when. Depending
on the answers and other circumstances, the officer should decide
if further investigation is warranted. If so, direct the driver to safely
exit the vehicle and escort him or her to the designated area for
further investigation. If not, permit the motorist to proceed.
Sobriety checkpoint pamphlets, questionnaires and occupant
protection booklets should be given to each motorist stopped
during the detection phase.
Also during the detection phase, the officer should see if the
occupants of the stopped vehicle are properly using required
safety restraints (including child safety seats). If a violation exists
a verbal reminder may be given.
Instruct officers to inspect the driver for the smell of alcoholic
beverages or other drugs, bloodshot eyes, fumbling fingers, slurred
speech, admission of drinking or drug use, abusive language,
inconsistent responses, etc. Be observant of the interior of the
vehicle for alcoholic beverage containers, drug paraphernalia or
other contraband, such as weapons, that are in plain view.
The motorist should be permitted to proceed on his/her way unless
the officer observes evidence of intoxication, or there is evidence
of another serious violation requiring immediate action.
Those persons suspected of impairment should be subjected to the
battery of Standardized Field Sobriety Tests. If impairment is
obvious and the blood alcohol level (BAC) is low, a Drug
Recognition Technician (DRT) should evaluate the subject. If a
DRT is not available, normal departmental policy for handling
impaired drivers should be followed.
A - 3
Searches of a motor vehicle, the driver, or passengers, shall be
conducted only when consistent with departmental policies or when
A motorist who wishes to avoid the checkpoint by legally turning
before enterning the checkpoint area should be allowed to do so
unless a traffic violation(s) is observed or probable cause exists to
take other action. The act of avoiding a sobriety checkpoint does
not consititute grounds for a stop.
An accurate and complete written evaluation report shall be
prepared for each sobriety checkpoint operation. Items in the
report should include but are not limited to:
- number of vehicles passing through the checkpoints
- number of motorists detained for Standardized Field
- average time delay for motorists
- 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 the effect on morale and degree of
- reaction of the motoring public to the sobriety checkpoint
B - 1
SOBRIETY CHECKPOINT GUIDELINES
The purpose of this policy is to provide guidelines for the physical
construction and operation of a sobriety checkpoint in order to maximize
the deterrent effect and increase the perception of "risk of apprehension"
of motorists who would operate a vehicle while impaired by alcohol or
It shall be the policy of this law enforcement agency to implement a
sobriety checkpoint program. This will be done as part of a
comprehensive enforcement program. To ensure standardization of this
program a clear and concise set of written guidelines has been developed
governing procedures on how checkpoints will be operated within this
To implement this policy this agency must:
. Satisfy federal, state and local legal requirements.
. Conduct checkpoints with a minimal amount of intrusion or motorist
. Assure the safety of the general public as well as law enforcement
. Provide for an objective site selection process based on relevant
. Provide for public information and education to maximize the
deterrent effect and heighten awareness of the impaired driving
B - 2
. Provide for a systematic procedure for data collection and after
impact analysis report to monitor and ensure standardization and
consistency of the sobriety checkpoint program.
. Officer selection should be based on experience and training.
Operational procedures will be covered during a briefing period
prior to each checkpoint.
III. DEPARTMENTAL GUIDELINES
Written guidelines, consistent with existing agency policies, prepared in
advance of the checkpoint program must:
A. Be approved by the agency's chief law enforcement official or
designee prior to commencement of the checkpoint.
B. Specify signing, safety equipment, warning devices, barriers, etc. that
will be used, their placement and proper use at the scene. This
specification will be consistent with applicable standards and
regulations. (See the relevant state or local manuals on traffic control
C. Specify the method for selecting motorists to be contacted, e.g.,
"every vehicle, every fifth vehicle," etc. to ensure objectivity.
D. Provide for an operational briefing of personnel prior to each
checkpoint. At this time designate assignments and respective
E. Specify dialogue and educational material to be used by checkpoint
F. Provide for the removal of vehicles to the predetermined area when
further investigation is required.
G. Public reaction to the use of sobriety checkpoints can be obtained by
several different methods. Recommended procedures for obtaining
1. Mail in surveys.
2. Verbal feedback from motorists at checkpoint site.
3. Periodic public opinion polls.
B - 3
A. Site Selection
This department must be able to objectively outline criteria utilized in the
site selection process:
1. Alcohol/Drug related traffic experiences.
a. Unusual incidence of alcohol/drug related crashes.
b. Alcohol/drug impaired driving violations.
c. Unusual number of nighttime single vehicle crashes.
d. Any other documented alcohol/drug related vehicular incidents.
2. Select locations which permit the safe flow of traffic through the
a. Consideration should be given to posted speed limits, traffic
volume and visibility.
b. Ensure sufficient adjoining space is available to pull vehicles off
the traveled portion of the roadway.
c. Consider other conditions that may pose a hazard.
3. The site should have maximum visibility from each direction and
sufficient illumination. If permanent lighting is unavailable ensure that
portable lighting is provided.
1. A sworn, uniformed officer will be assigned to provide on-scene
supervision of the checkpoint.
2. The checkpoint will be staffed by a sufficient number of uniformed
personnel to assure a safe and efficient operation.
C. ADVANCE NOTIFICATION
1. For the purpose of public information and education, this agency will
announce to the media that checkpoints will be conducted.
B - 4
2. This agency will encourage media interest in the sobriety checkpoint
program to enhance public perception of aggressive enforcement, to
heighten the deterrent effect and to assure protection of constitutional
3. This agency will provide advance notification of the checkpoint to
public safety agencies expected to be impacted.
D. MOTORISTS WARNINGS / SAFETY METHODS
1. Special care is required to warn approaching motorists of the sobriety
2. Basic equipment will include, but is not limited to:
a. Warning signs placed in advance of the checkpoint
b. Flares, fusees, or similar devices
c. Safety cones or similar devices
d. Permanent/portable lighting
e. Marked patrol vehicles
3. The use, placement and types of traffic control devices must comply
with federal, state, or local transportation codes.
E. CONTINGENCY PLANNING
Any deviation from the predetermined guidelines must thoroughly
document the reason for the deviation. (i.e. traffic backing up, intermittent
F. DATA COLLECTION AND EVALUATION
To monitor and ensure standardization and consistency of the sobriety
checkpoint program a systematic method of data collection will be
1. After action report may include, but is not limited to:
a. Time, date, and location of checkpoint.
b. Weather conditions.
c. Number of vehicles passing through checkpoint.
d. Average time delay to motorists.
e. Predetermined order of selecting motorists.
B - 5
f. Number and types of arrests.
g. Number of motorists detained for field sobriety testing.
h. Identification of unusual incidents such as safety problems/other
2. To assist in determining the effectiveness of a checkpoint operation, a
periodic impact analysis will include the following types of information.
a. Crash rate reduction.
b. Impaired driving offenses.
c. Impaired driving convictions
d. Public opinion survey to determine increased perception of
detection and apprehension of impaired drivers.