I am Joel Brand, and I defend DUI cases across California. If you were recently arrested after performing field sobriety tests on the side of the road, you may be replaying those moments and wondering whether your physical condition, your footwear, or the surface you stood on played a role in how the officer scored you. In this post I want to walk you through why those factors matter more than most people realize, and how an experienced defense attorney can use them.
What Field Sobriety Tests Are Actually Measuring
The three standardized tests officers use most often, the Horizontal Gaze Nystagmus, the Walk-and-Turn, and the One-Legged Stand, were designed under controlled laboratory conditions. On the street, in the dark, on uneven asphalt, wearing dress shoes from a dinner out, those same tests produce results that can be very misleading. The officer is counting "clues," and even one or two extra clues can push you into a "failed" result. What the officer often does not write in the report is that you were wearing heels, that you mentioned a knee replacement, or that the shoulder of the road was sloped.
The Footwear Problem
National Highway Traffic Safety Administration guidelines, the same guidelines officers are supposed to follow, actually state that a suspect wearing heels more than two inches high should be offered the chance to remove their shoes before performing the Walk-and-Turn or One-Legged Stand. Many officers skip this step. If you were in heels, wedges, dress boots, sandals with no ankle support, or even stiff work boots that night, that detail is worth documenting immediately while your memory is fresh. It goes directly to whether your performance on the test was a fair measure of anything. This is one of the issues I look for when I review the unfair field sobriety test defense in a case.
Pre-Existing Injuries and Medical Conditions
A prior knee surgery, a hip replacement, a herniated disc, plantar fasciitis, an inner ear condition, or even seasonal vertigo can all produce exactly the clues an officer marks as signs of impairment. Swaying, stepping off the line, putting a foot down early, using your arms for balance. These are all things a completely sober person with a balance disorder or a bad ankle does every single day. If you have any medical history that affects your balance, coordination, or gait, tell your attorney right away. Medical records, your doctor's letter, and even a brief declaration from you can become part of your mitigation documentation. California courts have seen cases where a medical condition explained away test performance that looked damning on paper.
Age and Physical Fitness
The research behind the standardized field sobriety tests was conducted primarily on younger, physically fit subjects. If you are over sixty, significantly overweight, or simply not athletic, your baseline performance on a one-legged stand or a heel-to-toe walk is going to be different from the baseline the test was calibrated against. Officers are supposed to take this into account, but in practice the same checklist gets applied to everyone. This is a real factor I raise when reviewing the mistakes police make at a DUI stop.
The Surface, the Lighting, and the Environment
NHTSA guidelines call for a reasonably dry, hard, level, non-slippery surface for the Walk-and-Turn and One-Legged Stand. Freeway shoulders rarely meet that standard. Gravel, painted asphalt, wet pavement, a slight grade, blinding headlights from passing cars, cold temperatures that cause muscle stiffness. Every one of these conditions can produce clues that have nothing to do with alcohol. When I pull the officer's dash-camera or body-camera footage, I am specifically looking at the surface and the lighting. These details sometimes do not appear in the written report at all. Review of that footage is also relevant to how officers document their observations more broadly.
Nerves and Anxiety Are Not Intoxication
Being pulled over at night, surrounded by flashing lights, with a stranger in uniform asking you to perform physical tasks while traffic rushes by, is genuinely stressful. Anxiety causes trembling, shortness of breath, difficulty following multi-step instructions, and loss of balance. Officers are trained to distinguish nervousness from impairment, but the honest truth is that the same outward signs overlap heavily. If you were visibly shaken during the stop, that is something worth noting in your defense.
Clothing Beyond Footwear
Tight skirts or slim-cut trousers limit your stride. A heavy coat changes your center of gravity. Work clothes after a long physical shift leave muscles already fatigued. If you were dressed for a formal event, for your job, or for the weather, the way you moved during those tests may reflect your outfit more than your BAC. This is a narrow point, but it is the kind of detail that can matter when an attorney is cross-examining the arresting officer at a preliminary hearing or at trial.
What the Officer Is Required to Ask Before the Tests Begin
Before administering the Walk-and-Turn or One-Legged Stand, an officer who is following proper protocol should ask whether you have any physical impairments, disabilities, or injuries that might affect your ability to perform the test. Many do not ask. If the officer failed to inquire and you have a known condition, that is a procedural shortcut that can affect how much weight a judge or jury gives the test results. The California DUI defenses guide covers the broader range of procedural challenges available, and this is one of the more overlooked ones.
How This Plays Into the Bigger Picture of Your Case
Field sobriety tests are just one piece of the prosecution's case. They are typically paired with a breath or blood result and the officer's observations. But if your test performance was affected by footwear, injury, age, or environment, it undermines the overall narrative that you were obviously impaired. A skilled attorney can argue that the officer's probable cause to arrest you was weaker than it appeared, which can matter for a motion to suppress evidence. It can also matter when a prosecutor is deciding whether to offer a reduction to a wet reckless or another lesser charge.
What You Should Do Right Now
Write down everything you remember about that night while it is still fresh. What shoes were you wearing. Did you mention any injuries or physical conditions to the officer. What did the ground feel like. Was it wet, sloped, gravelly. Were there bright lights in your eyes. Did the officer offer to let you remove your shoes. These details fade quickly, and they can matter. Also gather any medical records related to balance, joint, or neurological conditions. Bring them to your first meeting with an attorney.
Your Physical Condition Is a Legitimate Defense, Not an Excuse
I want to be clear about something. Raising these issues is not about making excuses. It is about holding the testing process to the standard it is supposed to meet. If the test was not administered properly, or if your physical situation made it an unfair measure of impairment, that is exactly what the law allows you to challenge. The role of a DUI attorney is to examine every part of the stop and the arrest and find where the process fell short. Physical and environmental conditions at the field sobriety tests are a legitimate and often overlooked place to start.
You can get a free written case analysis right here on this page. Call me directly at (888) 271-6644. I answer my own phone, 24/7. And if you want to keep reading, there is more from the DUI blog that may speak to your specific situation.