Drunk Driving in the Garden State: Understanding Why Police Conduct BAC Testing

Every now and again we are asked by clients and acquaintances alike what it is like to be arrested for drunken driving and if there are any tricks to avoiding being arrested for DWI. Quite frankly, the biggest trick — tried and true — is simply not to drink any liquor or use any drugs prior to getting behind the wheel of a motor vehicle in New Jersey. State and local law enforcement officers here in the Garden State are well known for their tenacity when performing a traffic stop that appears to be the result of drinking and driving.

This is not to say that a patrolman can just pull any motorist over on the merest suspicion that the individual has been drinking. It is a major part of our drunk driving laws that a policeman may not stop a driver simply on the assumption that the driver has consumed alcohol recently. In order for a driver to be stopped in any circumstance, the officer must witness a traffic infraction on the suspect’s part. But this can be something so minor, so inconsequential, that even failure to signal a turn or “rolling” through a stop sign without coming to a complete stop can set the stage for a police stop and a possible DWI arrest.

As New Jersey DWI-DUI defense lawyers, we can easily say that if a driver has not been drinking, then a routine traffic stop could end with a little as a warning, or perhaps the patrolman issuing a ticket for the infraction(s). But, should a driver exhibit any of the so-called typical signs of intoxication or impairment, then it could turn out to be a long day at police headquarters for that unlucky driver. This is why, and despite sounding flip, we always advise people not to have a drink if they plan to drive anywhere. Besides the statistical danger of injury, it’s just not worth the chance of being arrested and charged with driving under the influence of alcohol.

But once an officer has his suspicions that a motorist is drunk or impaired by prescription drugs, the gloves usually come off and process of determining intoxication will begin in earnest. Here in New Jersey, a driver is considered legally impaired by alcohol if that individual’s blood-alcohol concentration (BAC) is at or above 0.08 percent while operating a motor vehicle. In such cases, the motorist can be charged by police with DWI; and the local prosecutor can use that BAC measurement as evidence in court to prove that the driver is guilty of drunken driving.

The way a BAC test works is based on the legally recognized concept that alcohol consumed by a person is eventually absorbed into the individual’s bloodstream. During the absorption process, the molecular structure of the alcohol is not altered and remains intact as it circulates throughout the body, including the person’s lungs. A breathalyzer test — such as the Alcotest device — can detect the presence of alcohol in a person’s system and has become an accepted method for measuring BAC levels for purposes of obtaining a conviction in DWI cases.

Another method is more direct and involves taking a blood sample from the suspect. Either method of determining alcohol in the bloodstream can be used as evidence in a court of law. It is important to note that refusing a breathalyzer test or blood draw for the purpose of determining a driver’s BAC is also a chargeable offense in New Jersey. This is because New Jersey has what is known as the “implied consent” law, every motorist gives his or her “consent” to BAC testing whenever they receive their driver’s license. But this is a topic for another time.