(FSTs) are used by the police to establish probable cause for administering
a preliminary breath test or making a
California driving under the influence (DUI) arrest.
Unfortunately, FSTs are highly subjective and often unreliable. Even the
most trustworthy field sobriety tests are shown to be only 65-77% accurate
at detecting whether the driver is DUI.
Therefore, it is important for California drivers to understand the basics of FSTs
before they encounter them.
Standardized FSTs were developed after substantial research by the National Highway
Traffic Safety Administration (NHTSA) in order to determine the accuracy of FSTs.
Of all of the FSTs studied, the NHTSA found that three tests proved to
be most reliable-the Horizontal Gaze Nystagmus, the One Leg Stand, and
the Walk and Turn. These three FSTs became known as the "Standardized
Field Sobriety Tests."
Below is a quick summary of the three tests:
Stay tuned to tomorrow'
s blog post for information about additional California field sobriety tests!
Horizontal Gaze (Nystagmus): Officer positions a finger or pen about a foot from a driver's face,
moving it from side to side while watching their eyes for jerking or trembling
One Leg Stand: Driver stands with heels together, arms against their sides and counts
out loud while raising one leg six inches off the ground, testing their balance.
Walk and Turn: Officer instructs a driver to take nine to twelve heel-to-toe steps on
a line, turn and repeat them back, looking for mistakes or loss of balance.
California DUI Defense Attorneys will carefully review the circumstances in which any field sobriety tests
were given. In addition, they will determine whether the testing officer
adhered to the required protocols and has received the proper training.
If not, lawyers most often can get any testimony given by the testing officer
Further information about field sobriety tests and California DUI laws
can be found at the
California DUI Guide
website. Drivers are also encouraged to contact an
experienced DUI defense attorney
if they are arrested for DUI after a field sobriety test.