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Why are sobriety checkpoints not widely adopted as an enforcement strategy in the United States?
Accident Analysis and Prevention 35 (2003) 897–902
Why are sobriety checkpoints not widely adopted as an enforcement strategy in the United States? James C. Fell a,∗ , Susan A. Ferguson b , Allan F. Williams b , Michele Fields b a
Pacific Institute for Research and Evaluation, 11710 Beltsville Drive, Suite 300, Calverton, MD 20705-3102, USA b Insurance Institute for Highway Safety, 1005 North Glebe Road, Arlington, VA 22201-4751, USA Received 3 June 2002; accepted 7 June 2002
Abstract Sobriety checkpoints have been used by police in the United States for at least the past two decades to enforce impaired driving laws. Research has indicated that sobriety checkpoints are effective in reducing drinking and driving and alcohol-related fatal crashes. Despite this evidence, many police agencies have been unenthusiastic about using checkpoints. Information was collected from all 50 states plus the District of Columbia on the use of sobriety checkpoints. A total of 37 states and the District of Columbia reported conducting sobriety checkpoints at least once or twice during the year. Only 11 states reported that checkpoints were conducted on a weekly basis. Thirteen states do not conduct checkpoints either because of legal or policy issues. More detailed information was collected from five states that conduct checkpoints frequently and matched with information from five similar states that conduct checkpoints infrequently. States with frequent checkpoint programs had several common features such as program themes, support from task forces and citizen activist groups, use of a moderate number of police at the checkpoints, and use of all available funding mechanisms (federal, state, local) to support them. States with infrequent checkpoints claimed a lack of funding and police resources for not conducting more checkpoints, preferred saturation patrols over checkpoints because they were more “productive,” and used large numbers of police officers at checkpoints. Ways to overcome perceived barriers to checkpoint use are discussed. © 2003 Elsevier Science Ltd. All rights reserved. Keywords: Sobriety checkpoints; Driving while intoxicated; Effectiveness; Funding mechanisms; Police resources; Cost benefits
1. Introduction Laws dealing with driving while intoxicated (DWI) or driving under the influence (DUI), and the enforcement of these laws in the United States, serve as both general and specific deterrents to driving while impaired by alcohol. It is impossible for police to detect every impaired driver on the road. That is why it is important for enforcement strategies to increase the perceived risk of being caught in order to deter impaired driving in the first place. Sobriety checkpoints have been used by police in the United States for at least the past two decades as a strategy to enforce impaired driving laws. At sobriety checkpoints, police stop all vehicles, or a systematic selection of vehicles, to evaluate drivers for signs of alcohol or other drug impairment. To minimize public concern, signs are typically posted at the approaches to the checkpoints warning drivers that a checkpoint is ahead. Police officers in uniform approach drivers and identify themselves, describe the purpose ∗
Corresponding author. Tel.: +1-301-755-2746; fax: +1-301-755-2799. E-mail address: [email protected] (J.C. Fell).
of the stop, and ask the driver questions designed to elicit a response that will permit the officer to observe the driver’s general demeanor. Drivers who do not appear impaired are immediately waved on, while those who show signs of impairment are usually detained in a safe holding area where they are investigated further and either arrested or released. Research has indicated that sobriety checkpoints that are well publicized have high public visibility and can serve as a general deterrent to impaired driving. Studies in the early 1980s found significant decreases in alcohol-related crashes associated with sobriety checkpoint programs (Epperlein, 1985; Lacey et al., 1986; Voas et al., 1985). Later studies (Levy et al., 1988, 1990; Wells et al., 1992) confirmed that frequent, highly publicized checkpoint programs substantially reduced alcohol-related crashes 10–15%. A summary of the US literature examined nine studies through the early 1990s and concluded that “the cumulation of evidence supports the hypothesis that checkpoints reduce impaired driving” (Ross, 1992a). Two recent reports on the effectiveness of sobriety checkpoints have added convincing and consistent evidence. A demonstration program in Tennessee (“Checkpoint
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Tennessee”) was sponsored by the National Highway Traffic Safety Administration (NHTSA) to determine if highly publicized checkpoints conducted throughout the state on a weekly basis would have an effect on impaired driving in the state. The evaluation of the program, using interrupted time series, showed a 20% reduction in alcohol-related fatal crashes extending at least 21 months after conclusion of the formal program (Lacey et al., 1999). The other report was a review of the latest literature on the effectiveness of sobriety checkpoints and random breath testing in reducing motor vehicle crash injuries (Peek-Asa, 1999). Six studies were reviewed that met the study criteria of including an evaluation of checkpoints, with a control or baseline comparison. All six studies found that checkpoints were effective in reducing alcohol-related fatalities and injuries. Sobriety checkpoints have been challenged in US courts for their legality. In 1990, the US Supreme Court upheld the constitutionality of sobriety checkpoints in a case that challenged them under the Fourth Amendment to the Constitution, which protects against unreasonable searches and seizures (Michigan Department of State Police et al. vs. Sitz et al., 1990). The Court held that the interest in reducing the incidence of alcohol-impaired driving was sufficient to justify the brief intrusion occasioned by a properly conducted sobriety checkpoint. However, 12 states report that sobriety checkpoints are illegal based on state law. NHTSA has published numerous reports on the conduct of sobriety checkpoints. Research examining different alcohol-impaired driving law enforcement strategies showed that the proportion of all crashes involving alcohol declined an average of 28% in four communities that used publicized sobriety checkpoints compared with a 17% decline in communities that used only publicized roving patrols (or saturation patrols). There were no differences in effectiveness for checkpoint programs with small staffing levels (3–5 officers per checkpoint) compared with high staffing levels (8–12 officers), or for checkpoints that stayed in one location versus those that moved around (Stuster and Blowers, 1995). In an effort to promote the use of sobriety checkpoints in the states, NHTSA has issued guidelines to communities on conducting sobriety checkpoints (Compton, 1983; NHTSA, 1990) and has produced a law enforcement training video on sobriety checkpoints (NHTSA, 1999) and a how-to guide for planning and publicizing them (NHTSA, 2000). It also recently provided funding to five states to conduct demonstration sobriety checkpoints at least weekly throughout the state. Police and other officials have been skeptical of the cost benefit of sobriety checkpoints, but a recent study indicates that checkpoint programs can yield considerable cost savings (Miller et al., 1998). Despite the evidence supporting the increased use of sobriety checkpoints and guidance on how to conduct them, many police agencies have been unenthusiastic. In a prior study, Ross (1992b) explored reasons for the sporadic use of checkpoints. The main reasons were that checkpoints yield few arrests and were believed to be an inefficient use of
police resources; that checkpoints require more resources than most departments can afford; that the checkpoint task is boring, uncomfortable to do in inclement weather, and presents the risk of injury to police and motorists; that checkpoints inconvenience innocent motorists; that it is not fair to take such extraordinary measures to contact drinking drivers who have not gotten in trouble on the roads; and that there is little political support for checkpoints. All of these arguments were discussed and countered by Ross and have been addressed in a NHTSA (1993) brochure. Ten years later sobriety checkpoints are still underused, except in a minority of states. The present study provided the opportunity to re-address the question of why this is so. The approach taken was to attempt to determine why some states conduct checkpoints frequently while other states do not, identifying impediments to checkpoint use as seen by low-use states.
2. Methods In cooperation with the National Association of Governors’ Highway Safety Representatives, a survey questionnaire on sobriety checkpoint use was sent to each state’s highway safety office in June 2000. By the middle of July 2000, all 50 states and the District of Columbia had responded. Ten states were selected for in-depth study. Five reported frequent-use of sobriety checkpoints on a statewide basis and were geographically diverse. Five other states that reported infrequent-use of checkpoints were selected for comparison. Efforts were made to select high- and low-use states that were similar in population and geography. Inquiries were made as to who makes the decision to conduct checkpoints in the state, how they are funded, how they are publicized, how many police officers are typically used, opinions as to the effectiveness of sobriety checkpoints, the use of other enforcement strategies, and impediments to conducting more checkpoints. A specific protocol of 23 questions was used in each interview. Depending upon responses, follow-up questions to obtain additional details were frequently asked. Two typical questions are illustrated below: How are sobriety checkpoints typically publicized in your state? • • • • • • • •
Press releases. TV, radio announcements. Billboards. Posters, brochures. Newspaper articles (earned media). Newspaper/TV/radio (paid ads). Typically not publicized. Other. How often are they publicized?
• All the time (press releases).
J.C. Fell et al. / Accident Analysis and Prevention 35 (2003) 897–902
• • • • •
Most of the time. Just for certain large checkpoints. Just in certain cities/counties/jurisdictions. Just during holiday periods. Other.
Telephone and personal interviews were used to gather the data. At least two officials, and sometimes as many as four, in the state of interest were interviewed. In each state selected, in-depth interviews were conducted with at least one knowledgeable official from the State Office of Highway Safety, in addition to top-level police officials (e.g. commanders, chiefs, captains). Since only 11 states reported that checkpoints were conducted on a weekly basis, a follow-up interview was also conducted with an official in the State Highway Safety Office in all 11 of those states.
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weekly basis throughout the state. Another 13 states and the District of Columbia reported they conduct checkpoints once or twice a month. There were eight states that reported infrequent-use of checkpoints (every other month or only during major holiday periods) and five states that conduct them only when resources were available. Twenty states plus the District of Columbia reported that checkpoints are conducted in all counties and jurisdictions. Seventeen states reported some restrictions whereby checkpoints are conducted only in certain counties or jurisdictions. Twenty-seven states said that all police jurisdictions (state, local, sheriff) conduct checkpoints, whereas the remaining 10 states reported that only certain police jurisdictions conduct them. The 10 states chosen for further study are listed below. The results of the interviews conducted in the 10 states chosen for in-depth study are presented in Table 2.
Reasons for selection States with frequent sobriety checkpoints Georgia (large state, Southeast)
Indiana (large state, Midwest)
New York (large state, Northeast) Nevada (medium/small state, West)
Virginia (medium state, mid-Atlantic) States with infrequent sobriety checkpoints Alabama (medium state, Southeast) Ohio (large state, Midwest) Illinois (large state, Midwest) Arizona (medium state, West) Maryland (medium state, mid-Atlantic)
Conducts checkpoints on a weekly basis. All jurisdictions and all police agencies participate. One of five NHTSA checkpoint demonstration states. Conducts checkpoints on a weekly basis in most jurisdictions. Prosecutors do not allow them in some counties. All police agencies participate at some point during the year. Conducts checkpoints on a weekly basis. All jurisdictions and all police agencies participate at some point during the year. Conducts checkpoints at least once or twice a month in most counties. All police agencies participate at some point during the year. Conducts checkpoints weekly. All counties and all police agencies participate at some point during the year. Conducts checkpoints about once a month following Federal Section 410 Grant guidelines. Conducts checkpoints only during major holiday periods and only in certain counties. All police agencies participate. Conducts checkpoints only once a month statewide, every other week in city of Chicago. Conducts checkpoints only during major holiday periods and only in certain counties. Not all police agencies conduct them. Conducts checkpoints every other month and only in certain counties. Conducted by state and local police only.
3. Results
4. Other states with frequent sobriety checkpoints
The results of the initial survey of the states conducted in cooperation with the National Association of Governors’ Highway Safety Representatives are presented in Table 1. In summary, 37 states plus the District of Columbia reported they presently conduct sobriety checkpoints, and 13 reported they do not. Of the 37 states conducting checkpoints, only 11 states reported they conduct checkpoints at least on a
In-depth interviews were conducted not only in the states compared in Table 2, but also in the other states that reported conducting checkpoints weekly. In total, 11 states reported weekly checkpoints (AR, GA, HI, IN, KY, MS, NY, NC, SD, VT, and VA). The responses from these 11 states were markedly similar. For example, 10 of the 11 states (all but KY) believed that sobriety checkpoints were
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Table 1 Results of sobriety checkpoint survey of US states Are sobriety checkpoints presently conducted in your state? Yes (37 states plus DC)
No (13 states)
How frequently are sobriety checkpoints conducted in your state? Weekly (11 states) Once/twice a month (13 states plus DC) Every other month (four states) Only during major holiday periods (four states) Variable, depending upon resources available (five states) Where in your state are sobriety checkpoints conducted? In every county/jurisdiction (20 states plus DC) Only in certain counties/jurisdictions (17 states) Which police jurisdictions conduct sobriety checkpoints? All (state, local, sheriff, etc.) (27 states) State and local police only (six states) State police only (two states) Local police only (one state plus DC) Local police and sheriff only (one state)
AL, AZ, AR, CA, CO, CT, DE, DC, FL, GA, HI, IL, INa , KS, KY, ME, MD, MA, MS, MO, NE, NV, NH, NJ, NM, NY, NC, ND, OH, OK, PA, SC, SD, TN, UT, VT, VA, WV Checkpoints not conducted, but no legal impediment cited: AK Checkpoints illegal under state law: ID, LAa , MI, MN, OR, RI, TX, WA (violates state constitution); IA, MT, WY (statute authorizes roadblock stops for reasons that do not include sobriety checkpoints); WI (prohibited by statute) AR, GA, HI, IN, KY, MS, NY, NC, SD, VT, VA CA, CO, DC, FL, IL, KS, MO, NE, NV, NJ, NM, OK, PA, TN DE, MD, NH, UT AL, AZ, MA, OH CT, ME, ND, SC, WV AL, AR, CA, DE, DC, GA, HI, IL, KS, KY, ME, MS, NY, NC, OK, SC, SD, TN, UT, VT, VA AZ, CO, CT, FL, IN, MD, MA, MO, NE, NV, NH, NJ, NM, ND, OH, PA, WV AL, AZ, CA, CO, FL, GA, IL, IN, KS, KY, ME, MS, MO, NV, NM, NY, NC, OH, OK, PA, SC, SD, TN, UT, VT, VA, WV AR, CT, DE, MD, NH, NJ MA, ND DC, HI NE
a Since this survey was conducted, two decisions have changed the status of the law. In July 2000, sobriety checkpoints were held to be legal under the Louisiana Constitution; this overruled an earlier decision. In November 2000, an Indiana intermediate appellate court held that sobriety checkpoints violate the Indiana Constitution; in March 2002, the Indiana Supreme Court overruled the intermediate court and upheld sobriety checkpoints under the state constitution.
Table 2 Comparison of DWI programs in states that conduct checkpoints frequently and infrequently
Organization/support
Manpower usage Funding/cost effectiveness
Frequent-use states (GA, IN, NY, NV, VA)
Infrequent-use states (AL, OH, IL, AZ, MD)
In four frequent-use states, task forces recommended and supported checkpoint programs. These were statewide task forces in GA and NY; local in NV and IN.
In OH, AZ, and MD, some counties did not conduct checkpoints for lack of official support (i.e. because their prosecutors would not prosecute offenders arrested at checkpoints or elected officials objected to checkpoints).
Checkpoints are organized around a theme in all five frequent-use states.a In all five frequent-use states, checkpoints typically used a moderate number of officers (2–15). In four states, all available funding from state, local, and federal sources was used to pay for checkpoints. Officials in all five states indicated they would conduct more checkpoints if additional funding were made available. Officials in all five states believed checkpoints were a cost beneficial deterrent to DWI.
Public support
In all five states with frequent checkpoints, community coalitions and citizen activist groups like Mothers Against Drunk Driving (MADD) were highly supportive of checkpoints. Support for checkpoints among the general public was also very high (75–95% in favor) in four states (GA, IN, NY, NV).
In four states (OH, IL, AZ, and MD), 15 or more officers (30 in some instances) were typically used at checkpoints. Lack of funding and insufficient police resources were cited most commonly in infrequent-use states as a reason checkpoints were not conducted more often. AL, OH, and AZ preferred “saturation patrols” to checkpoints because they were thought to be as effective a deterrent as checkpoints and probably “more productive.” Officials in all five states believed checkpoints were effective and said they would do more checkpoints if they had more funding. Community coalitions and citizen groups generally have not militated for more frequent checkpoints in these states.
Only IL reported that a citizen’s group, the Alliance Against Impaired Motorists (AAIM) supported the increased use of checkpoints.
a In each state, the themes were highly publicized and provided an impetus for maintaining checkpoint operations. The themes were: “Operation Zero Tolerance” (GA), “Operation Pull-Over” (IN), “Project Zero” (NY), “Joining Forces” (NV), “Smart, Safe and Sober” (VA).
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effective as a general deterrent and 10 of 11 states (all but VA) said that public support for checkpoints was high. Seven of the 11 states reported using passive alcohol sensors at checkpoints to help detect impaired drivers (AR, GA, KY, MS, NY, VT, VA), but most said they only had a few of the devices and they were not used all the time. Seven states reported that at least three mechanisms were used to publicize checkpoints: press releases, radio/TV announcements, and newspaper articles (earned media). Nine states said that checkpoints were publicized all or most of the time.
5. Discussion Checkpoints are an effective enforcement tool but are underused in the United Sates. A few states do use them frequently, however, and comparison of these states with those that use them infrequently provides insight into what motivates their use and nonuse. State task forces appear to be an important factor encouraging checkpoints. In New York State, for example, local “Stop DWI” task forces manage and provide funding for checkpoints. The funding comes from fines and fees paid by drivers convicted of DWI. In Indiana, the Governor’s Council on Impaired and Dangerous Driving provides the leadership and training for checkpoints. The local Marion County Traffic System Partnership, consisting of police representatives, citizens, business representatives, etc., provides impetus to the checkpoint program in the Indianapolis area. States with frequent checkpoint programs also have officials who understand the importance of deterring alcoholimpaired driving irrespective of the arrest rate. They also have active citizens groups such as MADD to support the checkpoint effort and urge continuation and expansion of the program. Program themes are widely publicized and have high recognition, and there is perceived to be widespread public support for checkpoints. These appear to be the key ingredients associated with frequent-use of checkpoints. In contrast, states with infrequent checkpoints have few of these elements. Some of these states have DWI task forces, but they were not actively promoting checkpoints. None of these states appeared to receive much encouragement or pressure from citizen activist groups to conduct checkpoints. Several of the barriers to checkpoints elucidated in the Ross (1992b) study were not present, however. There was no mention by officials about injury risk for police officers at checkpoints, or that they were unfair to drinking or nondrinking motorists, or boring to the police as reasons why they were not conducted more frequently. In fact, none of the 16 states interviewed mentioned these as barriers to conducting checkpoints. There remains, however, the notion that checkpoints are unproductive because few are arrested, and that saturation patrols result in more arrests and are thus
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a superior enforcement strategy. In fact, checkpoints can achieve arrest rates as high or higher than other enforcement methods in addition to creating general deterrence (Voas, 1989). Lack of police resources and lack of funding were the main reasons given for not conducting more checkpoints. Many infrequent-use states are under the impression that 15, 20, or even 30 officers are needed at each checkpoint, and they tend to use 15 or more officers per checkpoint. However, it has been shown that as few as 2–5 officers can handle checkpoints without loss of effectiveness. In the frequent-use states smaller checkpoints, in terms of police resources, were the norm. There needs to be substantial educational effort in the police community on how sobriety checkpoints can be conducted safely, effectively, efficiently, and legally with a moderate number of police officers. The funding issue was raised both in frequent- and infrequent-use states. In states with few checkpoints, financial support was an issue. In states with many checkpoints, officials said they would do even more given financial resources. States with many checkpoints tended to use a combination of state, local, and federal funds, and this is one option. But federal funding alone appears adequate to support sobriety checkpoint programs. Various funding mechanisms from the 1998 Transportation Efficiency Act for the 21st Century (TEA-21) include the general Section 402 grant money to the states for all traffic safety programs each year, Section 410 Impaired Driving grant money if states meet certain criteria, Section 163 grant money if states pass a 0.08 blood alcohol concentration per se law, and Section 403 demonstration program grants. In states that fail to enact open container laws and repeat DWI offender laws, a portion of highway maintenance funds will be transferred automatically to pay for highway safety programs. This money could be used to fund sobriety checkpoint programs (Sections 154 and 164). This amounts to millions of federal dollars available to the states each year for use in sobriety checkpoint programs. Thus, if states do not want to invest nonfederal funds in checkpoints, there is sufficient federal grant money that could be used, but states have to take the initiative. In summary, states with and without frequent checkpoints are distinguished by motivational factors and by their approaches to using financial and manpower resources. In the frequent-use states, the motivation for checkpoints comes from a combination of support by task forces, citizen activist groups, police officials who understand the power of checkpoints as a deterrence strategy, and the public. In these states, police resources generally are used efficiently, and various sources of funding are tapped. In states with infrequent checkpoints, available funds often are not sought and too many police officers are used at checkpoints. Some of the barriers to checkpoints can be overcome through education and training. Enlightened task forces and citizen activist groups can provide the motivation to use this effective enforcement tool.
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Acknowledgements The authors wish to thank Barbara Harsha, Executive Director of the National Association of Governors’ Highway Safety Representatives, for her assistance in conducting the survey of the states and the highway safety offices from all 50 states, and the District of Columbia for providing the necessary information. Appreciation is also extended to the numerous police officials who were interviewed and provided candid and important information. This work was supported by the Insurance Institute for Highway Safety. The opinions, findings, and conclusions expressed in this publication are those of the author(s) and do not necessarily reflect the views of the Insurance Institute for Highway Safety.
References Compton, R. 1983. The Use of Safety Checkpoints for DWI Enforcement (HS-806-476). National Highway Traffic Safety Administration, Washington, DC. Epperlein, T. 1985. The Use of Sobriety Checkpoints as a Deterrent: an Impact Assessment. Arizona Department of Public Safety, Phoenix, AZ. Lacey, J., Jones, R., Smith, R. 1999. Checkpoint Tennessee: Tennessee’s Statewide Sobriety Checkpoint Program (HS-808-841). National Highway Traffic Safety Administration, Washington, DC. Lacey, J., Stewart, J., Marchetti, L., Popkin, C., Murphy, P., Lucke, R., Jones, R., 1986. Enforcement and Public Information Strategies for DWI General Deterrence: Arrest Drunk Driving—the Clearwater and Largo, Florida, Experiences (HS-807-066). National Highway Traffic Safety Administration, Washington, DC. Levy, D., Asch, P., Shea, D., 1990. An assessment of county programs to reduce driving while intoxicated. Health Educ. Res. 5, 247– 255.
Levy, D., Shea, D., Asch, P., 1988. Traffic safety effects of sobriety checkpoints and other local DWI programs in New Jersey. Am. J. Public Health 79, 291–293. Michigan Department of State Police et al. vs. Sitz et al., 1990. 496 US 444, 110 L.Ed.2d 412. Miller, T., Galbraith, M., Lawrence, B., 1998. Costs and benefits of a community sobriety checkpoint program. J. Studies Alcohol 59, 462– 468. National Highway Traffic Safety Administration, 1990. The Use of Sobriety Checkpoints for Impaired Driving Enforcement (HS-807-656), Washington, DC. National Highway Traffic Safety Administration, 1993. Sobriety Checkpoints: Point/Counterpoint (HS-807-916), Washington, DC. National Highway Traffic Safety Administration, 1999. Law Enforcement Training Video on Sobriety Checkpoints (HS-808-990), Washington, DC. National Highway Traffic Safety Administration, 2000. Saturation Patrols and Sobriety Checkpoints: a How-to Guide for Planning and Publicizing Impaired Driving Enforcement Efforts (HS-809-063), Washington, DC. Peek-Asa, C., 1999. The effect of random alcohol screening in reducing motor vehicle crash injuries. Am. J. Prevent. Med. 16 (1S), 57–67. Ross, H.L., 1992a. The Deterrent Capability of Sobriety Checkpoints: Summary of the American Literature (HS-807-862). National Highway Traffic Safety Administration, Washington, DC. Ross, H.L., 1992b. Reasons for non-use of sobriety checkpoints. Police Chief 59, 58–63. Stuster, J., Blowers, P., 1995. Experimental Evaluation of Sobriety Checkpoint Programs (HS-808-287). National Highway Traffic Safety Administration, Washington, DC. Voas, R.B., 1989. The relative effectiveness of checkpoints. In: Proceedings of the 11th International Conference on Alcohol, Drugs, and Traffic Safety. National Safety Council, Washington, DC, pp. 76–80. Voas, R.B., Rhodenizer, E., Lynn, C., 1985. Evaluation of Charlottesville Checkpoint Operations (HS-806-989). National Highway Traffic Safety Administration, Washington, DC. Wells, J.K., Preusser, D.F., Williams, A.F., 1992. Enforcing alcoholimpaired driving and seat belt use laws, Binghamton, New York. J. Safety Res. 23, 63–71.
Why are sobriety checkpoints not widely adopted as an enforcement strategy in the United States? James C. Fell a,∗ , Susan A. Ferguson b , Allan F. Williams b , Michele Fields b a
Pacific Institute for Research and Evaluation, 11710 Beltsville Drive, Suite 300, Calverton, MD 20705-3102, USA b Insurance Institute for Highway Safety, 1005 North Glebe Road, Arlington, VA 22201-4751, USA Received 3 June 2002; accepted 7 June 2002
Abstract Sobriety checkpoints have been used by police in the United States for at least the past two decades to enforce impaired driving laws. Research has indicated that sobriety checkpoints are effective in reducing drinking and driving and alcohol-related fatal crashes. Despite this evidence, many police agencies have been unenthusiastic about using checkpoints. Information was collected from all 50 states plus the District of Columbia on the use of sobriety checkpoints. A total of 37 states and the District of Columbia reported conducting sobriety checkpoints at least once or twice during the year. Only 11 states reported that checkpoints were conducted on a weekly basis. Thirteen states do not conduct checkpoints either because of legal or policy issues. More detailed information was collected from five states that conduct checkpoints frequently and matched with information from five similar states that conduct checkpoints infrequently. States with frequent checkpoint programs had several common features such as program themes, support from task forces and citizen activist groups, use of a moderate number of police at the checkpoints, and use of all available funding mechanisms (federal, state, local) to support them. States with infrequent checkpoints claimed a lack of funding and police resources for not conducting more checkpoints, preferred saturation patrols over checkpoints because they were more “productive,” and used large numbers of police officers at checkpoints. Ways to overcome perceived barriers to checkpoint use are discussed. © 2003 Elsevier Science Ltd. All rights reserved. Keywords: Sobriety checkpoints; Driving while intoxicated; Effectiveness; Funding mechanisms; Police resources; Cost benefits
1. Introduction Laws dealing with driving while intoxicated (DWI) or driving under the influence (DUI), and the enforcement of these laws in the United States, serve as both general and specific deterrents to driving while impaired by alcohol. It is impossible for police to detect every impaired driver on the road. That is why it is important for enforcement strategies to increase the perceived risk of being caught in order to deter impaired driving in the first place. Sobriety checkpoints have been used by police in the United States for at least the past two decades as a strategy to enforce impaired driving laws. At sobriety checkpoints, police stop all vehicles, or a systematic selection of vehicles, to evaluate drivers for signs of alcohol or other drug impairment. To minimize public concern, signs are typically posted at the approaches to the checkpoints warning drivers that a checkpoint is ahead. Police officers in uniform approach drivers and identify themselves, describe the purpose ∗
Corresponding author. Tel.: +1-301-755-2746; fax: +1-301-755-2799. E-mail address: [email protected] (J.C. Fell).
of the stop, and ask the driver questions designed to elicit a response that will permit the officer to observe the driver’s general demeanor. Drivers who do not appear impaired are immediately waved on, while those who show signs of impairment are usually detained in a safe holding area where they are investigated further and either arrested or released. Research has indicated that sobriety checkpoints that are well publicized have high public visibility and can serve as a general deterrent to impaired driving. Studies in the early 1980s found significant decreases in alcohol-related crashes associated with sobriety checkpoint programs (Epperlein, 1985; Lacey et al., 1986; Voas et al., 1985). Later studies (Levy et al., 1988, 1990; Wells et al., 1992) confirmed that frequent, highly publicized checkpoint programs substantially reduced alcohol-related crashes 10–15%. A summary of the US literature examined nine studies through the early 1990s and concluded that “the cumulation of evidence supports the hypothesis that checkpoints reduce impaired driving” (Ross, 1992a). Two recent reports on the effectiveness of sobriety checkpoints have added convincing and consistent evidence. A demonstration program in Tennessee (“Checkpoint
0001-4575/$ – see front matter © 2003 Elsevier Science Ltd. All rights reserved. PII: S 0 0 0 1 - 4 5 7 5 ( 0 2 ) 0 0 0 9 7 - 0
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Tennessee”) was sponsored by the National Highway Traffic Safety Administration (NHTSA) to determine if highly publicized checkpoints conducted throughout the state on a weekly basis would have an effect on impaired driving in the state. The evaluation of the program, using interrupted time series, showed a 20% reduction in alcohol-related fatal crashes extending at least 21 months after conclusion of the formal program (Lacey et al., 1999). The other report was a review of the latest literature on the effectiveness of sobriety checkpoints and random breath testing in reducing motor vehicle crash injuries (Peek-Asa, 1999). Six studies were reviewed that met the study criteria of including an evaluation of checkpoints, with a control or baseline comparison. All six studies found that checkpoints were effective in reducing alcohol-related fatalities and injuries. Sobriety checkpoints have been challenged in US courts for their legality. In 1990, the US Supreme Court upheld the constitutionality of sobriety checkpoints in a case that challenged them under the Fourth Amendment to the Constitution, which protects against unreasonable searches and seizures (Michigan Department of State Police et al. vs. Sitz et al., 1990). The Court held that the interest in reducing the incidence of alcohol-impaired driving was sufficient to justify the brief intrusion occasioned by a properly conducted sobriety checkpoint. However, 12 states report that sobriety checkpoints are illegal based on state law. NHTSA has published numerous reports on the conduct of sobriety checkpoints. Research examining different alcohol-impaired driving law enforcement strategies showed that the proportion of all crashes involving alcohol declined an average of 28% in four communities that used publicized sobriety checkpoints compared with a 17% decline in communities that used only publicized roving patrols (or saturation patrols). There were no differences in effectiveness for checkpoint programs with small staffing levels (3–5 officers per checkpoint) compared with high staffing levels (8–12 officers), or for checkpoints that stayed in one location versus those that moved around (Stuster and Blowers, 1995). In an effort to promote the use of sobriety checkpoints in the states, NHTSA has issued guidelines to communities on conducting sobriety checkpoints (Compton, 1983; NHTSA, 1990) and has produced a law enforcement training video on sobriety checkpoints (NHTSA, 1999) and a how-to guide for planning and publicizing them (NHTSA, 2000). It also recently provided funding to five states to conduct demonstration sobriety checkpoints at least weekly throughout the state. Police and other officials have been skeptical of the cost benefit of sobriety checkpoints, but a recent study indicates that checkpoint programs can yield considerable cost savings (Miller et al., 1998). Despite the evidence supporting the increased use of sobriety checkpoints and guidance on how to conduct them, many police agencies have been unenthusiastic. In a prior study, Ross (1992b) explored reasons for the sporadic use of checkpoints. The main reasons were that checkpoints yield few arrests and were believed to be an inefficient use of
police resources; that checkpoints require more resources than most departments can afford; that the checkpoint task is boring, uncomfortable to do in inclement weather, and presents the risk of injury to police and motorists; that checkpoints inconvenience innocent motorists; that it is not fair to take such extraordinary measures to contact drinking drivers who have not gotten in trouble on the roads; and that there is little political support for checkpoints. All of these arguments were discussed and countered by Ross and have been addressed in a NHTSA (1993) brochure. Ten years later sobriety checkpoints are still underused, except in a minority of states. The present study provided the opportunity to re-address the question of why this is so. The approach taken was to attempt to determine why some states conduct checkpoints frequently while other states do not, identifying impediments to checkpoint use as seen by low-use states.
2. Methods In cooperation with the National Association of Governors’ Highway Safety Representatives, a survey questionnaire on sobriety checkpoint use was sent to each state’s highway safety office in June 2000. By the middle of July 2000, all 50 states and the District of Columbia had responded. Ten states were selected for in-depth study. Five reported frequent-use of sobriety checkpoints on a statewide basis and were geographically diverse. Five other states that reported infrequent-use of checkpoints were selected for comparison. Efforts were made to select high- and low-use states that were similar in population and geography. Inquiries were made as to who makes the decision to conduct checkpoints in the state, how they are funded, how they are publicized, how many police officers are typically used, opinions as to the effectiveness of sobriety checkpoints, the use of other enforcement strategies, and impediments to conducting more checkpoints. A specific protocol of 23 questions was used in each interview. Depending upon responses, follow-up questions to obtain additional details were frequently asked. Two typical questions are illustrated below: How are sobriety checkpoints typically publicized in your state? • • • • • • • •
Press releases. TV, radio announcements. Billboards. Posters, brochures. Newspaper articles (earned media). Newspaper/TV/radio (paid ads). Typically not publicized. Other. How often are they publicized?
• All the time (press releases).
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• • • • •
Most of the time. Just for certain large checkpoints. Just in certain cities/counties/jurisdictions. Just during holiday periods. Other.
Telephone and personal interviews were used to gather the data. At least two officials, and sometimes as many as four, in the state of interest were interviewed. In each state selected, in-depth interviews were conducted with at least one knowledgeable official from the State Office of Highway Safety, in addition to top-level police officials (e.g. commanders, chiefs, captains). Since only 11 states reported that checkpoints were conducted on a weekly basis, a follow-up interview was also conducted with an official in the State Highway Safety Office in all 11 of those states.
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weekly basis throughout the state. Another 13 states and the District of Columbia reported they conduct checkpoints once or twice a month. There were eight states that reported infrequent-use of checkpoints (every other month or only during major holiday periods) and five states that conduct them only when resources were available. Twenty states plus the District of Columbia reported that checkpoints are conducted in all counties and jurisdictions. Seventeen states reported some restrictions whereby checkpoints are conducted only in certain counties or jurisdictions. Twenty-seven states said that all police jurisdictions (state, local, sheriff) conduct checkpoints, whereas the remaining 10 states reported that only certain police jurisdictions conduct them. The 10 states chosen for further study are listed below. The results of the interviews conducted in the 10 states chosen for in-depth study are presented in Table 2.
Reasons for selection States with frequent sobriety checkpoints Georgia (large state, Southeast)
Indiana (large state, Midwest)
New York (large state, Northeast) Nevada (medium/small state, West)
Virginia (medium state, mid-Atlantic) States with infrequent sobriety checkpoints Alabama (medium state, Southeast) Ohio (large state, Midwest) Illinois (large state, Midwest) Arizona (medium state, West) Maryland (medium state, mid-Atlantic)
Conducts checkpoints on a weekly basis. All jurisdictions and all police agencies participate. One of five NHTSA checkpoint demonstration states. Conducts checkpoints on a weekly basis in most jurisdictions. Prosecutors do not allow them in some counties. All police agencies participate at some point during the year. Conducts checkpoints on a weekly basis. All jurisdictions and all police agencies participate at some point during the year. Conducts checkpoints at least once or twice a month in most counties. All police agencies participate at some point during the year. Conducts checkpoints weekly. All counties and all police agencies participate at some point during the year. Conducts checkpoints about once a month following Federal Section 410 Grant guidelines. Conducts checkpoints only during major holiday periods and only in certain counties. All police agencies participate. Conducts checkpoints only once a month statewide, every other week in city of Chicago. Conducts checkpoints only during major holiday periods and only in certain counties. Not all police agencies conduct them. Conducts checkpoints every other month and only in certain counties. Conducted by state and local police only.
3. Results
4. Other states with frequent sobriety checkpoints
The results of the initial survey of the states conducted in cooperation with the National Association of Governors’ Highway Safety Representatives are presented in Table 1. In summary, 37 states plus the District of Columbia reported they presently conduct sobriety checkpoints, and 13 reported they do not. Of the 37 states conducting checkpoints, only 11 states reported they conduct checkpoints at least on a
In-depth interviews were conducted not only in the states compared in Table 2, but also in the other states that reported conducting checkpoints weekly. In total, 11 states reported weekly checkpoints (AR, GA, HI, IN, KY, MS, NY, NC, SD, VT, and VA). The responses from these 11 states were markedly similar. For example, 10 of the 11 states (all but KY) believed that sobriety checkpoints were
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Table 1 Results of sobriety checkpoint survey of US states Are sobriety checkpoints presently conducted in your state? Yes (37 states plus DC)
No (13 states)
How frequently are sobriety checkpoints conducted in your state? Weekly (11 states) Once/twice a month (13 states plus DC) Every other month (four states) Only during major holiday periods (four states) Variable, depending upon resources available (five states) Where in your state are sobriety checkpoints conducted? In every county/jurisdiction (20 states plus DC) Only in certain counties/jurisdictions (17 states) Which police jurisdictions conduct sobriety checkpoints? All (state, local, sheriff, etc.) (27 states) State and local police only (six states) State police only (two states) Local police only (one state plus DC) Local police and sheriff only (one state)
AL, AZ, AR, CA, CO, CT, DE, DC, FL, GA, HI, IL, INa , KS, KY, ME, MD, MA, MS, MO, NE, NV, NH, NJ, NM, NY, NC, ND, OH, OK, PA, SC, SD, TN, UT, VT, VA, WV Checkpoints not conducted, but no legal impediment cited: AK Checkpoints illegal under state law: ID, LAa , MI, MN, OR, RI, TX, WA (violates state constitution); IA, MT, WY (statute authorizes roadblock stops for reasons that do not include sobriety checkpoints); WI (prohibited by statute) AR, GA, HI, IN, KY, MS, NY, NC, SD, VT, VA CA, CO, DC, FL, IL, KS, MO, NE, NV, NJ, NM, OK, PA, TN DE, MD, NH, UT AL, AZ, MA, OH CT, ME, ND, SC, WV AL, AR, CA, DE, DC, GA, HI, IL, KS, KY, ME, MS, NY, NC, OK, SC, SD, TN, UT, VT, VA AZ, CO, CT, FL, IN, MD, MA, MO, NE, NV, NH, NJ, NM, ND, OH, PA, WV AL, AZ, CA, CO, FL, GA, IL, IN, KS, KY, ME, MS, MO, NV, NM, NY, NC, OH, OK, PA, SC, SD, TN, UT, VT, VA, WV AR, CT, DE, MD, NH, NJ MA, ND DC, HI NE
a Since this survey was conducted, two decisions have changed the status of the law. In July 2000, sobriety checkpoints were held to be legal under the Louisiana Constitution; this overruled an earlier decision. In November 2000, an Indiana intermediate appellate court held that sobriety checkpoints violate the Indiana Constitution; in March 2002, the Indiana Supreme Court overruled the intermediate court and upheld sobriety checkpoints under the state constitution.
Table 2 Comparison of DWI programs in states that conduct checkpoints frequently and infrequently
Organization/support
Manpower usage Funding/cost effectiveness
Frequent-use states (GA, IN, NY, NV, VA)
Infrequent-use states (AL, OH, IL, AZ, MD)
In four frequent-use states, task forces recommended and supported checkpoint programs. These were statewide task forces in GA and NY; local in NV and IN.
In OH, AZ, and MD, some counties did not conduct checkpoints for lack of official support (i.e. because their prosecutors would not prosecute offenders arrested at checkpoints or elected officials objected to checkpoints).
Checkpoints are organized around a theme in all five frequent-use states.a In all five frequent-use states, checkpoints typically used a moderate number of officers (2–15). In four states, all available funding from state, local, and federal sources was used to pay for checkpoints. Officials in all five states indicated they would conduct more checkpoints if additional funding were made available. Officials in all five states believed checkpoints were a cost beneficial deterrent to DWI.
Public support
In all five states with frequent checkpoints, community coalitions and citizen activist groups like Mothers Against Drunk Driving (MADD) were highly supportive of checkpoints. Support for checkpoints among the general public was also very high (75–95% in favor) in four states (GA, IN, NY, NV).
In four states (OH, IL, AZ, and MD), 15 or more officers (30 in some instances) were typically used at checkpoints. Lack of funding and insufficient police resources were cited most commonly in infrequent-use states as a reason checkpoints were not conducted more often. AL, OH, and AZ preferred “saturation patrols” to checkpoints because they were thought to be as effective a deterrent as checkpoints and probably “more productive.” Officials in all five states believed checkpoints were effective and said they would do more checkpoints if they had more funding. Community coalitions and citizen groups generally have not militated for more frequent checkpoints in these states.
Only IL reported that a citizen’s group, the Alliance Against Impaired Motorists (AAIM) supported the increased use of checkpoints.
a In each state, the themes were highly publicized and provided an impetus for maintaining checkpoint operations. The themes were: “Operation Zero Tolerance” (GA), “Operation Pull-Over” (IN), “Project Zero” (NY), “Joining Forces” (NV), “Smart, Safe and Sober” (VA).
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effective as a general deterrent and 10 of 11 states (all but VA) said that public support for checkpoints was high. Seven of the 11 states reported using passive alcohol sensors at checkpoints to help detect impaired drivers (AR, GA, KY, MS, NY, VT, VA), but most said they only had a few of the devices and they were not used all the time. Seven states reported that at least three mechanisms were used to publicize checkpoints: press releases, radio/TV announcements, and newspaper articles (earned media). Nine states said that checkpoints were publicized all or most of the time.
5. Discussion Checkpoints are an effective enforcement tool but are underused in the United Sates. A few states do use them frequently, however, and comparison of these states with those that use them infrequently provides insight into what motivates their use and nonuse. State task forces appear to be an important factor encouraging checkpoints. In New York State, for example, local “Stop DWI” task forces manage and provide funding for checkpoints. The funding comes from fines and fees paid by drivers convicted of DWI. In Indiana, the Governor’s Council on Impaired and Dangerous Driving provides the leadership and training for checkpoints. The local Marion County Traffic System Partnership, consisting of police representatives, citizens, business representatives, etc., provides impetus to the checkpoint program in the Indianapolis area. States with frequent checkpoint programs also have officials who understand the importance of deterring alcoholimpaired driving irrespective of the arrest rate. They also have active citizens groups such as MADD to support the checkpoint effort and urge continuation and expansion of the program. Program themes are widely publicized and have high recognition, and there is perceived to be widespread public support for checkpoints. These appear to be the key ingredients associated with frequent-use of checkpoints. In contrast, states with infrequent checkpoints have few of these elements. Some of these states have DWI task forces, but they were not actively promoting checkpoints. None of these states appeared to receive much encouragement or pressure from citizen activist groups to conduct checkpoints. Several of the barriers to checkpoints elucidated in the Ross (1992b) study were not present, however. There was no mention by officials about injury risk for police officers at checkpoints, or that they were unfair to drinking or nondrinking motorists, or boring to the police as reasons why they were not conducted more frequently. In fact, none of the 16 states interviewed mentioned these as barriers to conducting checkpoints. There remains, however, the notion that checkpoints are unproductive because few are arrested, and that saturation patrols result in more arrests and are thus
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a superior enforcement strategy. In fact, checkpoints can achieve arrest rates as high or higher than other enforcement methods in addition to creating general deterrence (Voas, 1989). Lack of police resources and lack of funding were the main reasons given for not conducting more checkpoints. Many infrequent-use states are under the impression that 15, 20, or even 30 officers are needed at each checkpoint, and they tend to use 15 or more officers per checkpoint. However, it has been shown that as few as 2–5 officers can handle checkpoints without loss of effectiveness. In the frequent-use states smaller checkpoints, in terms of police resources, were the norm. There needs to be substantial educational effort in the police community on how sobriety checkpoints can be conducted safely, effectively, efficiently, and legally with a moderate number of police officers. The funding issue was raised both in frequent- and infrequent-use states. In states with few checkpoints, financial support was an issue. In states with many checkpoints, officials said they would do even more given financial resources. States with many checkpoints tended to use a combination of state, local, and federal funds, and this is one option. But federal funding alone appears adequate to support sobriety checkpoint programs. Various funding mechanisms from the 1998 Transportation Efficiency Act for the 21st Century (TEA-21) include the general Section 402 grant money to the states for all traffic safety programs each year, Section 410 Impaired Driving grant money if states meet certain criteria, Section 163 grant money if states pass a 0.08 blood alcohol concentration per se law, and Section 403 demonstration program grants. In states that fail to enact open container laws and repeat DWI offender laws, a portion of highway maintenance funds will be transferred automatically to pay for highway safety programs. This money could be used to fund sobriety checkpoint programs (Sections 154 and 164). This amounts to millions of federal dollars available to the states each year for use in sobriety checkpoint programs. Thus, if states do not want to invest nonfederal funds in checkpoints, there is sufficient federal grant money that could be used, but states have to take the initiative. In summary, states with and without frequent checkpoints are distinguished by motivational factors and by their approaches to using financial and manpower resources. In the frequent-use states, the motivation for checkpoints comes from a combination of support by task forces, citizen activist groups, police officials who understand the power of checkpoints as a deterrence strategy, and the public. In these states, police resources generally are used efficiently, and various sources of funding are tapped. In states with infrequent checkpoints, available funds often are not sought and too many police officers are used at checkpoints. Some of the barriers to checkpoints can be overcome through education and training. Enlightened task forces and citizen activist groups can provide the motivation to use this effective enforcement tool.
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Acknowledgements The authors wish to thank Barbara Harsha, Executive Director of the National Association of Governors’ Highway Safety Representatives, for her assistance in conducting the survey of the states and the highway safety offices from all 50 states, and the District of Columbia for providing the necessary information. Appreciation is also extended to the numerous police officials who were interviewed and provided candid and important information. This work was supported by the Insurance Institute for Highway Safety. The opinions, findings, and conclusions expressed in this publication are those of the author(s) and do not necessarily reflect the views of the Insurance Institute for Highway Safety.
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