Understanding The Alcotest

While we await the return of DUI checkpoints to the Jersey Shore, the Law Office of Frederick P. Sisto is happy to provide tips to help you avoid a wrongful DUI conviction. A key to avoiding convictions is understanding how the Alcotest machine (formerly known as a Breathalyzer) works.

Recall from the June DUI tip that there is only one situation in which it might make sense to refuse to submit to breath-testing after being arrested for suspicion of DUI: if you have no prior DUI convictions and are substantially certain that your BAC is .15 or above. Once you submit to breath-testing, it is helpful to understand how the Alcotest works.

Your highest blood alcohol concentration (BAC) is contained at the end of your breath sample. This is why police are trained to encourage you to give the longest breath sample possible.

Your odds of providing a lower BAC reading are increased when you provide closer to the minimum samples required. The Alcotest machine measures the duration and volume of your breath samples. The sample provided must last for a minimum of 4.5 seconds and contain 1.5 liters of breath volume (1.2 liters for women over the age of 60). If you try to fake giving a sample, breathe out of the side of your mouth, etc., the machine will treat this as a refusal and you will be charged with both DUI and refusal. The same goes for providing a sample that lasts for less than 4.5 seconds. To increase your odds of providing the lowest BAC reading, you should follow all police instructions, including forming a tight seal around the mouthpiece, but should avoid providing a sample that lasts much more than 4.5 seconds. Only your lowest reading is admissible as evidence, so you should also provide as many breath samples as the police allow.

Stay tuned for additional tips, remember that the best DUI defense is a designated driver, and have a Happy New Year!