Police investigating a driver for Driving Under the Influence (DUI) in California usually conduct field sobriety tests before arresting the driver. These “tests”, which usually take place along a busy street or freeway with cars speeding past, shouldn’t even be called tests, because they’re designed to be failed. Their real purpose is to establish probable cause for a drunk driving arrest and to collect evidence for a court case. A driver subjected to a field sobriety test before being arrested for drinking and driving should contact a California criminal defense lawyer who specializes in successfully defending DUI / DWI cases.
There are two types of field sobriety tests – standardized and non-standardized. Three standardized tests recognized by the National Highway Transportation Safety Administration (NHTSA) are the horizontal gaze nystagmus test, the walk and turn test, and the one-leg stand test.
Another group of tests are such unreliable indicators of alcohol impairment that they aren’t even recognized by the NHTSA, but are still used by police. These include the Rhomberg balance test, the finger-to-nose test, the finger tap test, the hand pat test, the ABCs, the numbers backward test, and coin tricks.
The results of non-standardized field sobriety tests can be successfully challenged in court, because the tests aren’t recognized as accurate indicators of intoxication. Although these tests are designed to measure mental and physical impairment from alcohol use, many of these signs can be traced to physical problems that other than alcohol.
This aspect of drunk-driving defense is key for anyone facing a DUI / DWI: Experts agree that when it comes to alcohol intoxication, mental impairment always occurs before physical impairment. Some individuals have an alcohol tolerance that masks signs of physical impairment, but mental impairment can never be masked. If a driver is physically impaired but not mentally impaired, the physical impairment must come from a source other than alcohol, and a jury must acquit a driver on a charge of driving while impaired.
Remember, a jury must be convinced of the driver’s guilt beyond a reasonable doubt in order to return a drinking and driving conviction. An experienced DUI defense attorney knows that the inherent flaws in non-standard field sobriety tests pose great problems for the prosecution, and create doubt in the minds of jurors.
There are many reasons other than alcohol intoxication that may cause a driver to show signs of physical impairment, including injury, illness, fatigue, or nervousness. By taking a complete medical history, a lawyer who specializes in California DUI / DWI cases can determine whether any physical impairment stems from causes other than alcohol impairment. Ultimately, the results of field sobriety tests can be successfully challenged. No one who has ever fought a drunk driving case and won has ever regretted that fight.