Everything You Need to Know About Sobriety Tests

In today's world, as states and jurisdictions are increasing penalties for DUI and DWI offences, almost everyone has some type of story about being stopped by law enforcement officials. This could be a random stop, because of erratic driving, or because you are passing through a roadside checkpoint. Whether it's you, one or more of your friends, or potentially a family member, these charges are significant, and they are affecting more and more people.

However, what exactly happens when you are stopped for suspected drinking and driving? How do sobriety tests work? How will they affect you? Well, you've come to the right place - here is everything you need to know about sobriety tests.

Field Sobriety Tests

The first thing that's going to happen when you get pulled over is that you're going to have a field sobriety test administered by the law enforcement officer if they suspect you of being under the influence of alcohol or drugs. In the past, these tests could vary from state to state, but today they are standardized pretty much across the country. The Standardized Field Sobriety Test (SFST) is the name of the test that's endorsed by the body known as the National Highway Traffic and Safety Administration (NHTSA), and it consists of three key components.

1. The Horizontal Gaze Nystagmus (HGN) is a test where the officer will watch the suspected impaired driver's eyes, which react and twitch differently when you're impaired. The officer will look for changes in your eye's natural involuntary jerking, and check your ability to follow a moving object smoothly.

2. The Walk-and-Turn (WAT) test is probably the one that most people know of, and have maybe attempted themselves. It's remarkable how difficult it can be to complete such a seemingly simple task when you're impaired. What the WAT involves is having the DUI suspect perform a heel-to-toe walk of nine steps along a straight line, a one foot turn around, and then return the nine steps back toward the original starting point.

3. The One-Leg-Stand (OLS) test, which is another one that can be a fairly obvious indicator of a person who is impaired. What the officer will have the DUI suspect do in this case is stand on one foot, with the other foot six inches off the ground, for 30 seconds. It might not sound difficult, but it is for someone who is impaired by alcohol or drugs, because they will sway, balance themselves with their arms, or put the raised foot back down on the ground.

These three components of a field sobriety test, when used together, are not 100 percent accurate, but they are surprisingly effective, and accurate in over 91 percent of all cases.


Once a DUI suspect has completed the field sobriety test, if the officer still believes that they are impaired, a breath analysis test will be performed. The device used for the breath analysis is commonly referred to as a Breathalyzer.

A common question is whether or not you can turn down a Breathalyzer test. Well, you can, but it's a lot harder than it used to be, and it's generally not recommended to do so anymore. Many states and jurisdictions have moved to a system of "implied consent," meaning that you essentially exchange consent for submitting to a Breathalyzer test for your driving privileges in that jurisdiction.

"No refusal" enforcement is also becoming more and more commonplace. What this means is that the law enforcement officer can get electronic warrants from a judge on their mobile device. In the past, they had to get a paper warrant, which could take time and allowed for the DUI suspect to sober up before the test could be administered. Some people still elect not to take a Breathalyzer test if they determine that the stiff penalties for refusing them are still not as bad as multiple DUI or DWI charges.

Now, Breathalyzers are not perfect, and results are not infallible. They are not 100 percent accurate, and it is possible to challenge the results of one of these tests. A good DUI attorney will seek the maintenance records of the Breathalyzer. These devices need to be properly calibrated on a regular basis, and a failure to do so can render the results of the test invalid. The Breathalyzer needs to be proven as a reliable device in order for the results to be admissible in court. DUI lawyers will know all the details about field sobriety tests, and any potential areas where information and processes were missed.

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