Drivers in New Jersey are obligated by state law to provide breath samples to police when they suspect driving while intoxicated (DWI). Police throughout the state use a device known as the Alcotest to determine a driver’s blood alcohol content (BAC). We were involved in a case before the New Jersey Supreme Court in 2008, State v. Chun, which resulted in detailed rules for the use and maintenance of Alcotest devices. This includes a requirement of two separate breath tests. The New Jersey Appellate Division considered an appeal last fall from a DWI defendant who argued that the police did not follow the requirements set out in Chun. The court’s ruling addresses how precise police must be with regard to waiting between breath tests.
Prosecutors can prove, for the purposes of the DWI statute, that a defendant was under the influence of alcohol by presenting evidence of BAC at or above 0.08 percent. State law requires drivers to submit to breath testing, viewing the act of driving on New Jersey roads as giving implied consent. Refusal to provide breath samples upon request by police is a separate motor vehicle offense, punishable by a fine and driver’s license suspension.
The New Jersey Supreme Court’s ruling in Chun addressed numerous concerns about the Alcotest device’s accuracy and reliability. The court found that police must collect at least two samples, by which the driver exhales into a tube connected to the device. A special master appointed by the court noted the potential for contamination during the time between a driver submits their first breath sample and their second. To account for this, the device’s software locks everything down for two minutes to give the machine time to clear out the first breath sample.