Are Field Sobriety Tests Reliable?

The Houston Police Department employs field sobriety tests to judge whether a driver is intoxicated. When a blood test isn’t available, or if you refuse to give a sample, then a DWI case sometimes stands or falls based on the field tests.

Houston DWI Lawyers Tad Nelson & Amber Spurlock fully understand how subjective these tests are. We are more than ready to push back against any prosecution which relies on your inability to balance on one foot or walk in a perfectly straight line.

Let’s look at why some of the most common tests are unreliable.

Common Reliability Issues with Sobriety Tests

Some People Are Uncoordinated

Man Arrested for DWI - Field Sobriety Test

Two of the most common tests are Walk-and-Turn and One-Leg Stand. Both tests require coordination and proper balance to pull off. Unfortunately, some people simply lack coordination—and it has nothing to do with being intoxicated.

For example, balance and coordination both decline with age. And the decline begins to show up as soon as you’re in your 40s. You have less balance at 50 than you did at 40. And someone at 60 has less balance or coordination than they did at 50. If you can’t walk in a perfectly straight line, then that tells us nothing.

Some People Are Nervous

It can be hard to do even simple tasks when you are stressed. So much is riding on passing this field test. If you pass, you won’t be arrested. Fail, and you lose your Texas Driver License! Some people might struggle to tie their shoes under that kind of pressure.

On top of everything else, you might have friends in the car watching you as you take these tests. It all adds up to one difficult situation.

There Is No Baseline for Comparison

To gauge whether you are intoxicated, an officer would have to know how well you can walk or balance on one leg while completely sober. This is the “baseline” they would use to measure how coordinated you are on the night they pulled you over.

Unfortunately, officers have no reliable baseline to use. Unless they know you personally, they have no idea how you walk normally or whether you can balance for even a split second on one foot.

Your Eyes Could Be Sensitive to Light

Another popular field test is the Horizontal Gaze Nystagmus test, or HGN. Basically, an officer shines a light in your eyes and asks you to follow the light. If your eye movement is jerky, or you can’t follow direction, then the officer might assume you are drunk.

Of course, there are valid reasons you might not perform well on this test. Your eyes could be sensitive. Or you could have an eye infection or other problem which makes it difficult to follow the light.

Arrested with DWI Charges in Houston?

Reach Out to an Experienced Criminal Lawyer Today

Needless to say, these tests have nothing to do with being able to drive safely. You don’t need to balance on one leg to drive a car. If you or a loved one are facing prosecution for DWI related criminal charges in Houston, call Tad Nelson today at 713-489-7373 to speak with a member of our legal team. We offer free consultations and affordable, flexible payment options.