Could a Medical Condition Be the Real Reason You Failed Your Field Sobriety Test?

A police officer pulls you over, asks you to walk a straight line or stand on one leg, and decides you failed. But what if the reason you stumbled had nothing to do with alcohol or drugs? For Florida field sobriety test attorneys, this question comes up more often than most drivers realize. Field sobriety tests are built on the assumption that a sober body performs a certain way. That assumption falls apart the moment a medical condition enters the picture.

The Balance Tests Were Never Designed for Everybody

The Walk and Turn and the One Leg Stand ask a driver to do something most people rarely do on command: balance precisely, on a real or imagined line, while a stranger with a flashlight watches for mistakes. Officers are trained to look for swaying, using arms for balance, or stopping mid-test. According to the National Highway Traffic Safety Administration’s own training materials for these tests, factors unrelated to impairment can still produce those exact clues.

An inner ear infection, a herniated disc, a knee replacement, or even a case of vertigo can make heel-to-toe walking nearly impossible on a good day, let alone at 11 p.m. on the shoulder of a highway. Age and body weight matter too. A driver in their sixties or a driver carrying extra weight is simply not being measured against a fair baseline when the test assumes youthful coordination.

Why the Eye Test Raises Its Own Questions

The Horizontal Gaze Nystagmus test asks a driver to follow a pen with their eyes while an officer watches for involuntary jerking. That jerking, called nystagmus, is a real and well documented sign of alcohol consumption. It is also a symptom of certain neurological conditions, past head trauma, and some prescription medications that have nothing to do with a night out.

This overlap raises a fair question. If the same physical sign can point to two entirely different causes, how confident should anyone be in a roadside conclusion reached in under two minutes?

When Confusion Looks Like Intoxication

Diabetes deserves particular attention here. A driver experiencing hypoglycemia can appear disoriented, slur words, and struggle to follow instructions, symptoms that mirror what an officer is trained to flag as impairment. Someone in the middle of a panic attack, dealing with chronic fatigue, or recovering from a concussion can present the same way. None of these situations involve a blood alcohol concentration anywhere close to Florida’s legal threshold under Fla. Stat. § 316.1934, which defines the “normal faculties” that DUI law is meant to protect, including the ability to walk, talk, judge distances, and act in emergencies.

Building a Defense Around the Medical Facts

A thorough defense does not stop at questioning the officer’s observations. It should include a driver’s medical history, current prescriptions, and any records that explain the symptoms seen that night. Dashcam and body camera footage can also show whether the driver’s actual behavior matched what the report claims.

Field sobriety tests are subjective by design, and subjective tools miss context. If a medical condition was the true explanation behind a failed test, that distinction can change the entire trajectory of a case. Florida field sobriety test lawyers who understand both the science and the legal standard are often the ones best positioned to raise it.

Facing a DUI in Florida? Don’t hesitate to reach out to our team at FL DUI Group for guidance on next steps.

Source:

nhtsa.gov/sites/nhtsa.gov/files/2023-03/15911-SFST_Participant_Manual_2023-tag.pdf