Myth: Sobriety checkpoints constitute illegal search and seizure and are, therefore, unconstitutional.

Fact: In general, sobriety checkpoints can be thought of as being very similar to other accepted operations set up at airports to detect air passengers attempting to carry on weapons or bombs. Specifically, the U.S. Supreme Court on June 14, 1990, upheld the use of sobriety checkpoints to detect and deter impaired drivers. Previous appeals to the Supreme Court to review the constitutionality of such checkpoints had been declined, which allowed high state court rulings to stand. The June 14, 1990, ruling clearly upheld the constitutionality of such enforcement measures.

Myth: Sobriety checkpoints are only successful as specific deterrents and do not affect the general public's attitude about drinking and driving - only those who get caught in them.

Fact: Because of the heightened visibility checkpoints give to DWI law enforcement, they are especially valuable and effective as a general deterrent. Public information about the program and publication of arrests resulting from them further increases the general deterrent effect. If the public is aware the police will be conducting checkpoints, they tend to be much more careful about drinking and driving. They may drink less or find alternative transportation.

Myth: Sobriety checkpoints may be successful in Australia, but they have never been shown to be effective in the U.S.

Fact: Numerous studies in the U.S. demonstrate their effectiveness. For example, in Charlottesville, Virginia, reduction in impaired driving; New Jersey, reductions in alcohol-related crashes. A new study comparing community programs found that checkpoints, along with public information efforts, achieved significant deterrence. They have also been an important way of increasing safety belt usage when encouraged as part of the checkpoint procedures.

Myth: Sobriety checkpoints are easy for drinking drivers to avoid. They can merely turn around and detour around them or switch drivers before being stopped.

Fact: Most well-run checkpoints have a police officer down the road to observe such behavior. If drivers make a U-turn to avoid them, the police can follow the vehicle for a short distance to observe its operation. If the driver is observed switching places, they can pull the vehicle over. And even if drinking drivers do avoid the checkpoint, they may drive more cautiously because they are aware of active enforcement efforts.

Myth: Many drunk drivers do not exhibit impairment obvious enough to be detected at checkpoints, and police often do not detect these drivers.

Fact: While even thoroughly trained officers will not detect 100 percent of the drinking drivers, the police can use passive alcohol sensors, PAS, to help them detect those who are impaired. These passive sensors detect alcohol on the breath of the drivers while they are speaking to the officer. They can be calibrated so that a person who has truly had only one drink would probably not be detected, but will serve as a valuable "extension" of the officer's nose to help him determine who should be examined more closely for impairment.

Myth: Sobriety checkpoints are not needed more than once or twice a year in any community.

Fact: Most sobriety checkpoints must be run frequently to realize the desired effect in a community. They must be visible on a frequent basis in a community to maximize effectiveness. Once media coverage declines, frequency is even more important to maintaining effectiveness.

Myth: Sobriety checkpoints are very expensive to operate and yield very little in terms of arrests.

Fact: Sobriety checkpoints have been successfully run in California and Ohio with only three to four police officers. Most checkpoints yield more arrests for DWI/DUI per officer duty hour than normal patrols.

Myth: Sobriety checkpoints hold people up for long periods of time and cause huge traffic jams.

Fact: Well-conducted sobriety checkpoints generally delay drivers for no more 30 seconds, and cause no traffic problems. If traffic does back up, police are instructed to relieve congestion and then resume stopping cars in a predetermined pattern.

Myth: People don't like the use of sobriety checkpoints to detect and deter impaired drivers. They consider them a form of police harassment and an invasion of privacy. For that matter, they don't think they should be forced to wear safety belts, either.

Fact: Public opinion polls indicate just the opposite. Both recent surveys and polls throughout the 1980s and 1990s show that 70-80 percent of those polled are in favor of more sobriety checkpoint use to combat drunk driving. In fact, public support tends to increase as communities experience checkpoint use. Opponents of sobriety checkpoints tend to be those who drink and drive frequently and are concerned about being caught. In those same polls, 81 percent of adults also favor mandatory safety belt use laws.

Myth: Sobriety checkpoints really aren't necessary for adequate DWI enforcement programs.

Fact: Recent research substantiates the fact that checkpoints and aggressive public information efforts are essential to achieve deterrence of impaired driving. Checkpoints also provide a means of increasing awareness for safety belt use. Agencies are able to use checkpoints to favorably recognize sober drivers and passengers using seatbelts and to encourage non-users to buckle up before proceeding.

SOURCE: Mothers Against Drunk Driving and the National Highway Traffic Safety Administration.