FIELD SOBRIETY TESTING - MORE THAN MEETS THE EYE

Almost all DUI investigations include having a Californiatest given the complexity of theinstructions.
DUI suspectperform various balance and coordinationThe one leg stand is the easiest test to administer,
tests. These tests arereferred to as field sobrietybut for somesuspects, the hardest to perform. Being
tests or FST's. The theory behindthese tests is thatasked to place your handsat your sides and balance
they test a person's ability to divideattention. Drivingon one foot while keeping the opposite legperfectly
is portrayed as a divided attentiontask. One has tostrait and look down at your feet can be hard to do
both operate the automobile and also payattention toby theside of the road under the stress of a law
other cars, pedestrians, and traffic controls on theenforcement detention at
road.3:00 in the morning. I had one trial where I asked the
There are several FST's. The most common are theofficer todemonstrate this test. The officer
horizontal gazenystagmus, walk and turn, one legstruggled, shaking and hoppingbefore the jury. He
stand, Rhomberg balance, finger tonose, alphabet,failed the test, but said it was due to beingnervous in
and number count. Only three of these tests,court. Why did the officer fail to give my client
thehorizontal gaze nystagmus, walk and turn, andthesame excuse?
one leg stand arerecognized by the National HighwayNHSTA's manual claims that if the three SFST's are
Traffic and Safety Administrationperformed correctlyand scored correctly, than they
(NHSTA) as having a statistical validity. These threecan have an accuracy rate of 91% forpredicting a
tests arecalled Standardized Field Sobriety TestsBAC of .08 or above. These studies are
(SFST's)ofquestionable validity because they were all
The horizontal gaze nystagmus test consists of theconducted by lawenforcement agencies under
arresting officerasking the DUI suspect to keep theirunrealistic control, sample and verificationconditions. It
head still and follow a stimulussuch as a pen or fingeris important to emphasize that the 91% rate
while the officer moves it in front of theirface. Thewouldonly apply in a perfect investigation where the
officer is looking to see if the eyeballstests were donecorrectly. In the vast majority of
jerkinvoluntarily (nystagmus). This is the SFST thatcases, a good DUI defenseattorney can find the
has the greatestaura of scientific validity. However, indefects to help undermine the value of thisevidence
reality, it is junkscience. There are some people whoin the prosecution's case.
have nystagmusthat is natural or caused by a medicalThere are common misunderstandings of the role of
condition. The arrestingofficer can cause nystagmusFST's. Manypeople believe that FST's can show
by moving the stimulus too fast, holding itout tooimpairment or prove that a suspecthas a certain
long, or holding it too close to the suspect's face.blood alcohol level. The proper role of the FST'sas
Also, jerking motions by the arresting officer cantestified to by the creator of the FST's is to help the
causenystagmus. As a result, this test is rarelyarrestingofficer decide to arrest the DUI suspect and
performed correctlyand properly by arresting officers.take the DUI suspect tohave a chemical test
The walk and turn is a deceptively simple test, but inperformed. That is really the only purposefor FST's.
reality it iscomplex to administer. Giving the properNevertheless, many prosecutors and others continue
instructions anddemonstrating the test take practicetoinsist that the test performance on its own is
and experience. Failure tostart the person off on thesufficient forconviction.
correct foot can sabotage the entire testand set theIt critical for the DUI defendant to obtain a DUI
person up for failure. Minor sins like raising armsmorelawyer whounderstands the proper role and
than six inches for balance are counted against theweaknesses of field sobriety tests andcan
testsubject. There are many places to makeeffectively communicate these issues to juries and
mistakes. Soberpeople make many mistakes on thisjudges.