In all 50 states, drivers younger than 21 are covered by laws that prohibit driving with any measurable alcohol. An Institute study finds that awareness of these so-called zero tolerance laws is limited among young drivers. Awareness varies to some extent according to the enforceability of the specific laws in effect in various states. Researchers surveyed 17-20 year-olds in California, New Mexico, and New York — three states in which research has shown differences in the enforceability of zero tolerance laws and the extent of enforcement.
California's law is easiest to enforce (see "Zero-tolerance enforcement varies among states," March 11, 2000). A preliminary breath test is enough to prove a zero tolerance offense, and violations can be written at the roadside without taking a driver into custody. In contrast, New Mexico's law cannot be enforced independently of the DWI law because the tests that legally establish a driver's blood alcohol concentration (BAC) can be conducted only if the driver is arrested for DWI. There's no such legal impediment in New York, but police say they don't enforce the zero tolerance law very much because of the paperwork burden involved in citing offenders.
In all three states, teenagers' awareness of zero tolerance laws is limited. When teenagers were asked if there is a drinking and driving law that applies only to younger drivers, just 60 to 70 percent of the teens in California and New York indicated awareness of such laws. Awareness is particularly limited in New Mexico, where only a third of the teenagers said they're aware of the law.
Many teens who know about zero tolerance laws said they don't think enforcement is very frequent. Californians are somewhat more likely to think the laws are often enforced (63 percent), compared with New Mexicans (56 percent) and New Yorkers (53 percent). California teens aware of the law also are more likely to think that penalties are always applied when offenders are caught and that penalties could include license suspension.
Data on zero tolerance license suspensions confirm that police officers in California are enforcing the law and applying penalties more often than police in either New Mexico or New York. "Young drivers have to know about zero tolerance laws and they must perceive there's a good chance they will get caught for violations, if the laws are going to work," says Susan Ferguson, the Institute's senior vice president for research.
Now that all states have adopted zero tolerance laws, Ferguson says the focus needs to be on making such laws easier to enforce. In states like New Mexico, changes to the laws that govern BAC testing may be required. States like New York might benefit from shorter and simpler citation procedures.
Police then must enforce the laws in practice. Few programs in any state target apprehending young drivers with low BACs. Passive alcohol sensors can make detection easier, and conducting checkpoints where teens congregate could help send the message that zero tolerance laws are being enforced.