COLUMBUS, OHIO Thirty-seven states use sobriety checkpoints to fight drunken driving, but fewer than a third of them do so routinely, according to a study released Wednesday.
The study was done by the Insurance Institute for Highway Safety, which says sobriety checkpoints may be the best way for police to fight drunken driving. The institute is a nonprofit research organization funded by auto insurance companies.
Earlier research by the institute showed that alcohol-related fatal crashes can be reduced by 20 percent when publicized checkpoints are conducted frequently, said Sue Ferguson, senior vice president for research at the Insurance Institute, based in Alexandria, Va.
The latest study found that 11 states Arkansas, Georgia, Hawaii, Indiana, Kentucky, Mississippi, New York, North Carolina, South Dakota, Vermont, Virginia conducted checkpoints frequently, defined as at least once a week.
The 26 other states, including Ohio, that said they set up checkpoints did so about once a month, at major holidays, or when money and personnel were available.
Alaska reported that it did not conduct checkpoints even though state law did not prohibit them.
The 12 remaining states said state laws barred them from setting up checkpoints, despite a U.S. Supreme Court ruling in 1990 that upheld the constitutionality of properly conducted checkpoints.
"Until our society changes, the only defense we have to combating this violent crime is vigilant enforcement and education," said Jeff Runge, head of the National Highway Traffic Safety Administration. "Checkpoints provide that marriage."
States where checkpoints are frequent reported that community task forces and pressure from groups such as Mothers Against Drunk Driving influenced whether and how often checkpoints were conducted.
Law enforcement officials in states that do not conduct checkpoints often said they were too expensive and yield too few arrests to be worth the time, energy and resources, the study found.
"They're missing the point," Ferguson said. "What makes checkpoints effective is that they're more likely to prevent the offense in the first place, whether or not they lead to many arrests."
Civil liberties advocates argue that checkpoints violate the Fourth Amendment's protection against unreasonable search and seizures. But the Supreme Court has held that protecting the public outweighs the brief intrusion of the checkpoints.
Sobriety checkpoints have been used to enforce drunken driving laws for the past 20 years. At a typical checkpoint, signs are posted, warning drivers that police are ahead.