Impaired Driving

Driving Under the Influence (DUI)/Driving While Intoxicated (DWI) and Other State Laws

• DUI/DWI Laws
• Identifying Alcohol Impairment
• Key State Laws Enacted to Prevent Impaired Driving
• State Impaired Driving Laws

Driving Under the Influence (DUI)/Driving While Intoxicated (DWI) Laws

The terms “Driving under the influence” (DUI) and “Driving while intoxicated” (DWI) refer to state laws that make it illegal to drive with a certain blood alcohol concentration (BAC)—the amount of alcohol found in an individual’s blood. The terms are often used interchangeably to mean driving while impaired by alcohol or other drugs.

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Identifying Alcohol Impairment

Presence of alcohol is determined by measuring a person’s BAC. This process is usually conducted using a breathalyzer test. As an individual’s BAC increases, his/her mental efficiency decreases. Definite impairment begins in the range of .03 to just below .10. (A BAC level of .10 means that alcohol makes up one-tenth of one percent of the person's blood.)

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Key State Laws Enacted to Prevent Impaired Driving

Strong, consistently enforced laws are critical to the success of impaired driving prevention and deterrence efforts. Research indicates that the different types of laws summarized below help reduce the incidence of impaired driving.

Illegal Per Se Laws make it illegal in and of itself to drive a motor vehicle with a BAC concentration at or above an established level. All 50 states and the District of Columbia have per se laws defining it as a crime to drive with a blood alcohol concentration at or above a proscribed level, .08 percent. Research indicates that virtually all drivers show impairment in driving ability at .08 BAC, and the majority exhibit serious deterioration. Virtually all highway safety organizations and transportation safety agencies support .08 BAC, and in October 2000, Congress passed .08 BAC as the national standard for impaired driving regulations.

Dram Shop/Social Host Liability Laws state that a person who serves alcoholic beverages to intoxicated individuals may be liable for the damages caused by such individuals. In some states, a server may also be liable for injuries sustained by intoxicated individuals.

Minimum Legal Drinking Age (MLDA) Laws make it illegal for individuals younger than 21 to purchase, possess or consume alcoholic beverages or to misrepresent their age to obtain such beverages. All states and the District of Columbia have MLDA laws.

Zero Tolerance Laws make it illegal for drivers younger than 21 to drive with any measurable amount of alcohol in their system—regardless of the BAC limit for drivers over 21. Many states set the limit for drivers under 21 at .02 BAC or below to help reduce legal challenges based on claims that mouthwash, gum or cold medicine can be responsible for a positive but very low BAC measurement. However, there is no evidence that such substances affect the standard breath analysis tests when conducted properly or that other challenges to the accuracy of alcohol detection equipment are valid. By late 1999, all states plus the District of Columbia had zero tolerance laws for youth.

Open Container Laws prohibit the possession of any open alcoholic beverage container and the consumption of any alcoholic beverage in the passenger area of a motor vehicle. In 1998, the Federal government took steps to encourage states to enact open container laws by passing the Transportation Equity Act for the 21st Century (TEA-21), which required states to enact open container laws by October 1, 2000 or lose a portion of their Federal-aid highway construction funds. To avoid having their funds transferred to other safety activities, states must certify that they comply with Federal requirements and that their open container law is in effect and being enforced. By June 2007, 43 states and the District of Columbia complied with Federal terms of this law.

Administrative Suspension or Revocation Laws involve license suspension or revocation following conviction for impaired driving. ALR laws give state officials the authority to immediately suspend the license of any driver who fails an objective test (based on a BAC concentration of .08) or refuses to take a BAC test. ALR allows law enforcement and driver licensing authorities to revoke or suspend a driver’s license swiftly, without long delays, while the driver awaits a criminal trial. Some states may restore driving privileges on a limited basis due to demonstrated hardship, as determined by the courts. Depending on the state, suspensions range from seven days to six months for first-time offenders and longer for repeat offenders. As of June 2007, 41 states and the District of Columbia have administrative license suspension laws in place.

Repeat Intoxicated Driver Laws establish a minimum penalty for individuals convicted of a second or subsequent offense for driving while intoxicated or driving under the influence. Laws require a minimum of one-year driver’s license suspension; expect that all motor vehicles of repeat intoxicated drivers be impounded or immobilized for a specified period during the license suspension period, or require the installation of an ignition interlock system on all motor vehicles of such drivers for a specified period after the suspension is completed; ensure the mandatory assessment of the offender’s degree of alcohol abuse and referral to treatment as appropriate; and establish a mandatory minimum sentence. As of January 2006, 39 states and the District of Columbia were in compliance with Federal requirements that set the parameters for repeat intoxicated driver intervention activities.

Vehicle and License Plate Sanctions affect the vehicles or license plates of DUI/DWI offenders. Actions states can take include the following:

• Vehicle impoundment
• Suspension of vehicle registration
• Vehicle confiscation
• Vehicle forfeiture (sale of an offender’s vehicle)
• Vehicle immobilization (bars offender from using his or her car)
• Special license plates or plate markings (permit use of a vehicle by family members of convicted DUI/DWI offenders)
• Ignition interlock (device that measures alcohol concentration in the breath and is attached to a vehicle's ignition system; a driver must have a BAC below a certain level in order to start the vehicle)

As of March 2005, 44 states had laws that can affect the vehicles or vehicle plates of offenders. Check with a State Department of Transportation to determine the exact nature of the laws in its jurisdiction.

High-BAC Laws focus attention on drivers with a BAC of .15 or greater.  Enhanced penalties include increased driver license sanctions, vehicle or license plate impoundment or immobilization, mandatory assessment and treatment, close supervision, use of ignition interlock devices, fines and fees, and imprisonment or home detention (electronic monitoring). According to Mothers Against Drunk Driving, 40 states have high-BAC laws on their books.

Sobriety Checkpoints allow police officers to stop vehicles, or a specific sequence of vehicles (e.g., every fifth vehicle), at a predetermined fixed location to detect drivers who are impaired by alcohol and/or other drugs.  As of January 2006, sobriety checkpoints were allowed in 39 states.

Alcohol Exclusion Laws allow insurance companies to deny reimbursement to hospitals for treatment to those who are injured while impaired by alcohol or any drug not prescribed by a doctor at the time of their injury. These laws can actually prevent health care providers from administering screening and brief intervention (SBI) activities when they are needed most.  During SBI, physicians or other health professionals administer simple screening tests or questionnaires to determine whether a patient has an alcohol problem. Depending on the severity of the problem, physicians may conduct brief interventions—short counseling sessions to discuss problem drinking and its health risks—with patients in the emergency room. These sessions may last anywhere from a few minutes to an hour. As of January 2006, 37 states and the District of Columbia had alcohol exclusion laws, and since 2001, five states have repealed or amended these laws.

For information on impaired driving prevention laws in your state, visit the Mothers Against Drunk Driving’s Alcohol-Related Laws Web site.

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Selected State Impaired Driving Laws

¹Drivers usually must demonstrate special hardship to justify restoring privileges during suspension, and then privileges often are restricted.

²The 0.08 per se BAC law in Michigan contains a sunset clause which states that the legal BAC will revert to 0.10 on October 1, 2013.

³In New York, administrative license suspension lasts until prosecution is complete.

⁴In Tennessee, municipalities and counties can prohibit passengers from possessing an open container.

Sources:

Insurance Institute for Highway Safety. (November 2008). DUI/DWI Laws November 2008. Arlington, VA.

Mothers Against Drunk Driving (MADD). (2005). Alcohol-Related Laws Full Report by Law. Irving, TX.

National Highway Traffic Safety Administration. (March 2004). Traffic Safety Facts Laws-.08 BAC Illegal per se Level. Washington, DC:US Department of Transportation.

National Highway Traffic Safety Administration. (January  2006). Traffic Safety Facts Laws-Administrative License Revocation. Washington, DC: US Department of Transportation.

National Highway Traffic Safety Administration. (March 2005). Traffic Safety Facts Laws-Open Container Laws. Washington, DC: US Department of Transportation.

National Highway Traffic Safety Administration. (January  2008). Traffic Safety Facts Laws-Repeat Intoxicated Driver Laws. Washington, DC: US Department of Transportation.

National Highway Traffic Safety Administration. (March 2005). Traffic Safety Facts Laws-Vehicle and License Plate Sanctions. Washington, DC: US Department of Transportation.

For further information about your state’s impaired driving laws, go to your State Department of Transportation.

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