What is a preliminary alcohol screening device?

On Behalf of | May 19, 2023 | Criminal Defense

A preliminary alcohol screening device and a Breathalyzer are both used to measure a person’s blood alcohol content, but they differ in terms of their intended purpose, accuracy and use in law enforcement.

Anyone who’s facing drunk driving charges should understand a few key points about these testing devices so they can determine if there’s anything they should bring up as part of their defense strategy.

Purpose of the PAS and Breathalyzer

A PAS device is primarily used as an initial screening tool by law enforcement officers during field sobriety tests to determine if a person has been driving under the influence of alcohol. It provides a quick and approximate measure of a person’s BAC. If the PAS device indicates that the person may be intoxicated, the officer may proceed with an arrest and request a more accurate test, such as a breath or blood test.

A Breathalyzer, on the other hand, is a more accurate device used to measure a person’s BAC, typically after an arrest has been made. Breathalyzer results are often admissible in court as evidence of a person’s intoxication and can be used to support DUI charges.

Can both tests be used in court?

While both devices are used by law enforcement, a PAS device is more commonly used during roadside sobriety checks, as it provides a quick, approximate measure of a person’s BAC. A Breathalyzer is typically used at a police station or a mobile testing unit after an arrest has been made, providing a more accurate and legally admissible BAC measurement. 

Because of the accuracy concerns of a PAS device, the results of that test aren’t admissible in court. Breathalyzer test results are admissible. Working with someone familiar with these matters can help you to learn about what options you have for your defense strategy.

Ramos & Del Cueto, PLLC can provide experienced and dedicated assistance if you find yourself in need of help. Call 210-761-6004 or use the contact form below to contact our firm immediately.