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Impaired Driving Laws, Enforcement and Prevention

Driving while impaired refers to operating a motor vehicle while under the influence of alcohol. It is defined in the United States as a blood alcohol content (BAC) greater than or equal to 0.08% (mass of alcohol per volume of blood in the body). More than 10,000 people were killed in alcohol-impaired driving crashes in 2012, accounting for 31% of all U.S. traffic-related fatalities. In 2010, alcohol-impaired driving crashes were associated with nearly one in five of the traffic-related fatalities of children through age 14 years. Among those fatalities, more than half were passengers of vehicles with drivers who had BACs greater than or equal to 0.08%. Although the focus historically has been on alcohol impairment, drug-impaired driving is receiving increased attention from agencies and policy makers.

A host of effective strategies can be used to help address alcohol-impaired driving. These include strengthening impaired driving laws and enforcement efforts, education and awareness campaigns, and the use of technology (e.g., ignition interlocks) to prevent impaired drivers from operating vehicles. All states have laws against driving while impaired. Some states are using strategies, such as sobriety checkpoints, to further discourage impaired driving. Some are using campaigns such as “Drive Sober or Get Pulled Over” and “Buzzed Driving is Drunk Driving,” which combine increased enforcement efforts with advertising. The advertising is used to discourage impaired driving by making motorists aware that it is socially unacceptable and they can be pulled over and arrested for driving while impaired. Other strategies that can help address the problem include

  • High visibility enforcement
  • Prompt license revocation or suspension
  • Ignition interlocks for persons convicted of driving while intoxicated
  • License plate or registration confiscation
  • Vehicle impoundment or immobilization
  • Designated driver programs
  • Alcohol server training programs
  • Courts that address driving while intoxicated/driving under the influence repeat offenders through sanctions combined with drug and alcohol testing, treatment, and follow-up care and monitoring

Related Transportation and Heath Tool Indicators

How can this strategy result in health benefits?

  • Reduce motor vehicle-related injuries and fatalities

How has this worked in practice?

New Mexico’s Comprehensive Impaired-driving Program

The New Mexico Department of Transportation obtained funds from NHTSA in 2004 for a comprehensive state level impaired driving program. The program ran from 2005 to 2009, initially in five target counties, with a sixth county added in 2007. It included statewide media campaigns, an interagency leadership team, and increased, high visibility enforcement efforts and prosecutorial training. Program effectiveness was measured using driving while intoxicated crash, injury, and fatality rates, arrest rates, and conviction rates; blood alcohol concentration patterns; and public awareness. The results demonstrated effectiveness of the statewide and targeted efforts. Alcohol-involved fatal crashes decreased by 36.5% in those counties participating in the program, compared with a 31.6% decrease for the state as a whole. Alcohol-impaired fatal crashes decreased by 35.8% in the focus counties, compared with a 29% decrease for the state, which contrasted sharply with a 6.9% decrease in neighboring states for the same time period. New Mexico dropped from having the seventh highest alcohol-related fatality rate in the United States in 2004, before program implementation, to having the 19th highest rate in 2009.

Where can I learn more?

NHTSA provides statistics about impaired driving, materials for campaigns against impaired driving, and case studies of effective practices to stop impaired driving.

The CDC’s Injury Prevention & Control, Motor Vehicle Safety website includes resources on topics ranging from safety for older adult drivers to safety for pedestrians and motorcycle safety. It also has state data, cost and policy information. Within that website are the CDC’s Motor Vehicle Safety Costs pages, which include information on cost data and prevention policies. CDC Injury Prevention & Control: Motor Vehicle Safety - Impaired Driving includes data and statistics for crashes involving impaired drivers, research, and policy recommendations, including a CDC/NHTSA evaluation of key features of interlock programs and the use of interlocks in 28 states from 2006–2011. Within that website are the CDC’s Motor Vehicle Safety Ignition Interlock pages.

The Governors Highway Safety Association (GHSA) addresses the issue of driving while impaired, maintains up-to-date charts of alcohol- and drug-impaired driving laws and all state highway safety laws, discusses strategies for prevention of impaired driving and enforcement of laws, and sets a policy on impaired driving.

Mothers against Drunk Driving (MADD) is the nation’s largest nonprofit working to protect families from impaired driving and underage drinking. MADD also supports impaired driving victims and survivors.

NHTSA provides statistics about impaired driving, materials for campaigns against impaired driving, and case studies of effective practices to prevent impaired driving. NHTSA’s Countermeasures That Work report assists state highway safety offices in selecting science-based traffic safety countermeasures for major highway safety problem areas, including impaired driving.

The Guide to Community Preventative Services website includes resources about interventions to reduce alcohol-impaired driving.

Evidence base

Bergen G, Pitan A, Qu S, Shults RA, Chattopadhyay SK, Elder RW, Sleet DA, Coleman HL, Compton RP, Nichols JL, Clymer JM, Calvert WB, Community Preventive Services Task Force. Community Preventive Services Task Force. Publicized sobriety checkpoint programs: a community guide systematic review American Journal of Preventative Medicine 2014;46(5):529-39.

Bernat DH, Dunsmuir WTM, Wagenaar AC. Effects of lowering the legal BAC to 0.08 on single-vehicle-nighttime fatal crashes in 19 jurisdictions. Accident Analysis & Prevention 2004;36(6):1089-97.

Campostrini S, Holtzman D, McQueen DV, Boaretto E. Evaluating the effectiveness of health promotion policy: Changes in the law on drinking and driving in California. Health Promotion International 2006;21(2):130-5.

Erke A, Goldenbeld C, Vaa T. The effects of drink-driving checkpoints on crashes - A meta-analysis. Accident Analysis & Prevention 2009;41(5):914-23.

Hanson DJ. Alcohol Problems and Solutions. State University of New York; 2013.

National Highway Traffic Safety Administration (NHTSA). 2012 Motor Vehicle Crashes: Overview. Washington, DC: NHTSA, U.S. DOT. DOT HS 811 856; 2013.

National Highway Traffic Safety Administration (NHTSA). Alcohol-Impaired Driving. Washington, DC: NHTSA, U.S. DOT. DOT HS 811 870; 2013.

National Highway Traffic Safety Administration (NHTSA). The Nation’s Top Strategies to Stop Impaired Driving. Washington, DC: NHTSA, U.S. DOT. DOT HS 910 712; 2007.

Ramirez A, Lacey JH, Tippetts AS. New Mexico’s comprehensive impaired-driving program: A case study. Washington, DC: NHTSA, U.S. DOT. DOT HS 811 986; 2014.

Wagenaar AC, Maldonado-Molina MM. Effects of drivers’ license suspension policies on alcohol-related crash involvement: long-term follow-up in forty-six states. Alcoholism: Clinical and Experimental Research 2007;31(8):1399-406.