FSTs - Walk & Turn / One Leg Stand

Every part of a DUI arrest must be examined to provide an excellent
 defense, and criminal attorney John Guidry has been doing just that
since 1993.  No discussion of DUI arrests would be complete without
talking about FSTs.  Just because an officer sees you driving away from
 a bar, late at night, and stops you for weaving, doesn't give an officer the
 right to request Field Sobriety Tests (FSTs). The police may detain a
suspect longer than necessary to issue a traffic citation and may request field sobriety
exercises when that Officer has a reasonable suspicion of
criminal activity. Cresswell v. State of Florida, 564 So.2d 480, 481 (Fla. 1990)
“[P]robable causefor a DUI arrest must be based upon more than a belief that a driver has consumed alcohol; it must arise from facts and circumstances that show a probability thata driver is impaired by alcohol or has an unlawful amount of alcohol in [his] system”State v. Kliphouse, 771 So. 2d 16, 29 (Fla. 4th DCA 2000).  But, if the court determines that probable cause existed for requesting the tests, there is still the issue of whetheror not the tests are admissible as they may have been administered improperly,or more specifically that they must be given by the officer in the prescribed,standardized manner (as defined by the National Highway Traffic Safety Administration- NHTSA).

FSTs are designed to detect blood alcohol content (BAC) which is then used by
the officer along with other information to make an arrest decision.  Remember
that it is not illegal to drink and drive, but it is to drive with "normal
faculties impaired" by alcohol or drugs.  But, FSTs do not test ``normal
faculties'', but are divided attention exercises  designed to show if a subject
has a BAC of .08% or higher. Normal abilities are highly resistant to alcohol
because they consist of well-learned skills. FSTs are designed to overload
normal senses to check for unlawful blood alcohol levels. The relationship
between FSTs, BAC and impairment is complex; as BAC increases so
does impairment, but the relationship is a variable one. FSTs are designed
to allow officers to make a speedy and safe arrest decision at roadside
without the use of special equipment.  Unfortunately, all studies on FSTs
have been conducted under laboratory settings; there have been no
adequate field studies done to date.

The term Field Sobriety "Test" is sometimes replaced by the term "exercise",
because the use of the words ``test'', ``pass'' and ``fail'' is misleading to
the jury, depending on the results sought to be introduced. If the proper
predicate is laid for the introduction of FSTs as scientific evidence, clearly
such words are appropriate (rarely is a proper scientific predicate laid for
FSTs). If such evidence is presented in the form of non-scientific observations,
the use of such words could mislead the jury by causing them to attach a
scientific credibility to non-scientific results.  But even if the predicate is
not laid for the admission of FSTs as "scientific" evidence, evidence of any of
the physical tests administered in DUI cases is often admissible as
non-scientific evidence of impairment.  This is because the tests can be used to
measure defendant's balance, coordination and mental agility, or show whether
defendant's coordination has been impaired by the consumption of alcohol.

We're going to review two of the most popular tests (third being the Horizontal Gaze Nystagmus Test, or HGN  test), the Walk and Turn (W&T), and the One Leg Stand (1LS).  Both the W&T and the 1LS require adequate lighting and flat surface for each test. For the W&T, there must be hard, dry and level ground, and a line which the officer can manufacture if there is not one available. Persons over the age of sixty-five, more than fifty pounds overweight, or with back, leg or middle ear problems are not candidates for the three-test battery and should be given the HGN only. The order in which the tests are given is not important. Failure to adhere to the
proper procedures causes the test to lose its standardization and thus its

The proper procedures for conducting the W&T are, first, the suspect assumes a
heel to toe position on a real or imaginary line, with arms at sides, while
instructions are given. On command, subject takes nine heel to toe steps on the
line, then turns around keeping one foot on the line, counting out loud each
step. Subject then returns using nine heel to toe steps. Subject keeps eyes open
and watches feet.

On the W&T, there are eight clues of impairment which the officer "scores",
these eight clues break down into two initial clues dealing with the starting of
the test,  1) failure to keep balance while listening to instructions, and 2)
starting before instructions are finished (i.e., suspect starts walking before
officer says "begin"). The remaining six clues apply during the walking phase of
the test, 3) stopping while walking to reacquire balance, 4) not touching heel
to toe, 5) stepping off line, 6) using arms for balance, 7) losing balance while
turning, and 8) incorrect number of steps.  Less than two clues means a BAC of
under .08%.

The proper procedures for the One Leg Stand are as follows. Subject stands with
heels together, arms at sides, and raises either leg about six inches off the
ground while counting from ``1001'' to ``1030''. Subject keeps eyes open and
watches foot.

On the 1LS, there are four clues, one each for 1) swaying while balancing, 2)
hopping, 3) using arms for balance, and 4) putting foot down. Less than two
clues means a BAC of under .08%. More than the minimum clues on all tests means
a BAC greater than .08%.  Many scientific studies have concluded that this test
is inaccurate, especially when it comes to number 1) swaying and
number 3) using arms for balance.  Why, you ask?  Because in every study of
completely sober people, practically EVERYONE swayed and used their arms.  So,
how can those be a good 'clue' if all human beings exhibit that behavior, sober
or drunk? 

There exists no scientific study that links FSTs to driving impairment, and many
studies dispute any link FSTs have to impairment.  Of course, that hasn't stopped
law enforcement from using these tests.   FSTs are poor predictors of
actual behind the wheel driving, as we have no idea as to the 'baseline
performance level' of a suspect. So, assuming a person has had nothing to drink,
how would they perform on the One Leg Stand? Then, test their performance after
X number of drinks, you've established a 'baseline performance level'.  While
FSTs may have some accuracy when a suspect is extremely drunk, say three times
the legal limit, FSTs have a horrible track record in predicting impairment of
lesser BAL levels.  For example, one Florida study found that the W&T test
yielded over 52% false positives, the One Leg Stand yeilding over 40% false
positives. In other words, the officers conducting these tests in lab studies
were wrong about a suspects impairment 40-50% of the time! Could you imagine a
pregnancy test or cancer test having such a high false positive rate?  Yet
citizens are arrested daily based on such 'tests'.  (See "Field Sobriety Tests:
Are they Designed for Failure?, by Cole, Sl, Nowaczyk, R., Percept Mot. Skills,
1994, p. 79).  Don't be overwhelmed by what appears to be a great case for the
State when reading over a one sided police report, call criminal attorney John
Guidry so you can sit down with him, for free(!), to discuss how to fight your
arrest.  Did we mention the initial consultation is free? 
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