DRINKING DRIVERS MISSED AT SOBRIETY CHECKPOINTS

Objective: Sobriety checkpoints are an effective deterrent to alcohol- impaired driving although a substantial proportion of drinking drivers who pass through checkpoints are missed. The present study was design ed to determine the extent to which police officers correctly identify individuals with blood alcohol concentrations (BACs) at or above 0.05 % at checkpoints, and if there are characteristics of drivers, vehicle s or checkpoints that are associated with decreased chances of detecti on. Method: To determine which drivers are likely to be missed, driver s not detained by police for additional sobriety evaluation were inter viewed and voluntary breath samples were provided at 156 sobriety chec kpoints in North Carolina. Results: More than 50% of the drivers with BACs in excess of 0.08% and almost 90% of drivers with BACs in excess of 0.05% were not detained by officers. For drivers with BACs of 0.05% or higher, women and those 35 or younger were more likely to be misse d than were men and older drivers. Drivers without passengers were mor e likely to be missed than those with passengers. Drivers were also mo re likely to be missed during weekend checkpoints. Similar results wer e found for drivers with BACs at or above 0.08%. Conclusions: Alerting police officers to characteristics of drinking drivers more likely to be missed may improve detection rates. In addition, passive alcohol s ensors could improve the effectiveness and efficiency of sobriety chec kpoints in detecting drinking drivers.