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California DUI Field Sobriety Testing is Generally Not That Trustworthy

The objective of most honest forensic toxicologists in the field of California DUI investigation is to gather objective and comprehensive
information in order to form a trustworthy opinion about impairment, intoxication or sobriety.

Perhaps the best California Drunk Driving indicator of possible impairment appears to be a trustworthy blood alcohol test. California DUI Chemical
tests can objectively and accurately determine the driver BAC within the margin of error of the testing method and instrument. From this analysis, a
California DUI forensic opinion can be given on driving impairment based on scientific studies.

California DUI Field sobriety (non-chemical) tests are less trustworthy, and often are a poor indicator of impairment or sobriety. One of the reasons
for this is the inherent error in subjective evaluations of an individual whose normal performance is unknown.

In a North Carolina study, more than 50% of the drivers with BACs in excess of 0.08% and almost 90% of drivers with BACs in excess of 0.05% were not
detained by officers at a sobriety checkpoint. [Wells JK, Greene MA, Foss RD, Ferguson, S.A., Williams, A.F., Drinking Drivers Missed at Sobriety
Checkpoints, J Stud Alcohol, 1997, Sep;58(5):513-517, p. 513.]

In another study, police officers viewed drinkers on video and were asked to determine whether the target drinker had been drinking alcohol, whether
it was 'okay ' to serve the target another drink, and whether the target drinker was 'okay' to drive. The test did not include sober drinkers, or
drinkers below a 0.08% BAC (that is, the targeted range was between 0.08%-0.16%). Most police officers had difficulty determining whether the subjects at
the lower levels had been drinking. They even had difficulty deciding whether the subjects in the 0.15%-0.16% range had been drinking, let alone whether
those people should drive a car. [Brick, J., Carpenter, J.A, The Identification of Alcohol Intoxication by Police, Alcohol Clin Exp Res., 01, Jun;25(6):850-855, p. 850.]

California DUI Field Testing Limitations
Although California DUI field sobriety (non-chemical) tests are less reliable than chemical tests in determining BAC, non-chemical tests are still used as a tool to:

* Provide a California DUI officer probable cause for the stop or arrest.
* Help in assessing possible physical or mental impairment at a time close to driving.
* Determine some causal relationship between alcohol and California driving behavior.

California DUI Test Studies
Non-chemical evaluations of California DUI impairment or BAC can take several forms.
California DUI Field Sobriety tests can be conducted in any of the following studies:

* A research study.
* A controlled study.
* An uncontrolled study.

Some types of California DUI studies may include laboratory tests, correlation studies, and field studies such as driving behavior indicators or measurements of mental and physical ability. California DUI Lawyers generally examine whether proper California DUI studies have been conducted.


Types of California DUI Acrobatics & Gymnastics

California DUI Field sobriety tests (FSTs), alternatively referred to as field sobriety 93exercises 94 (FSEs) have been used for years to assist the California DUI field officer in making a California Drunk Driving arrest decision.

Many California DUI tests or California Drunk Driving Police tricks have been used:

* Asking distracting/interrupting California DUI police
questions.
* Finger to nose.
* Finger count test.
* Reciting or writing the alphabet, with signature and time and
date.
* Counting backwards from numbers as high as 100.
* Tracing (a paper-and-pencil exercise).
* Romberg Balance test.
* Romberg Balance test combined with Finger to Nose.
* Nystagmus ( 93HGN 94).
* One leg stand.
* Line walk.
* Hand Pat.
* Picking up coins.
* Recitation of date and time or the spelling of California.
* Standing heel to toe.

A California DUI Lawyer will usually question the validity and regularity of many of these California DUI FST's.


Standardized and Non-Standardized California DUI FST's

The United States Department of Transportation, National Highway Traffic Safety Administration (NHTSA) studied several field sobriety tests starting in 1975, with the results being published in 1977.

Three California DUI field sobriety tests were purportedly determined to have a good correlation with impairment when used together (provided that they are administered in strict compliance with the testing protocols). The three tests have come to be referred to as Standardized Field Sobriety Tests or SFSTs. The three SFSTs the research validated were:

* Horizontal Gaze Nystagmus.
* Walk and Turn.
* One Leg Stand.

In actual practice, California DUI police officers regularly offer a battery of tests that include exercises that have not been validated.
California DUI Lawyers often have a field day with irregular & improperly administered California DUI FST's.

Not All California DUI Field Tests Have Been Studied

Some of the California DUI tests have been explored by California DUI Lawyers for their degree of reliability. For example, there is considerable data available to a California DUI Lawyer on the nystagmus (HGN) test and the Romberg test, since these tests have clinical origins.

However, not all of the various California DUI field exercises have been studied for reliability, or have been validated as meaningful indicators of alcohol impairment. Several California Drunk Driving tests are used even without proper validation or any scientific study to support their use by California DUI officers. A number of California DUI tests merely look for changes in divided attention ability. Improper validation and lack of proper studies are viable attacks for a California DUI Lawyer.