Driving While under the Influence of Drugs

March 27th, 2011 Richard Blevins Posted in Driving under the Influence of Drugs, Field Sobriety Tests No Comments »

In Georgia you can be arrested and prosecuted for driving a motor vehicle under the influence of drugs.  Some law enforcement officers have completed the Advanced Roadside Impaired Driving Enforcement (A.R.I.D.E.) course and are trained to conduct additional tests to determine if someone should be arrested for operating a vehicle under the influence of drugs.  I just completed the course, the same one that law enforcement officer complete in their training.  I learned about the three additional tests that are used on the roadside to determine if someone is under the influence of a drug.  Drugs are broken down into seven categories:  CNS Depressants, CNS Stimulants, Hallucinogens, Dissociative Anesthetics, Narcotic Analgesics, Inhalants, and Cannabis.To test for a subject for operating a vehicle DUI-Drugs, the look at general indicators and place them into a matrix to determine what drug you are under the influence of.   They are required to administer the Horizontal Gaze Nystagmus (HGN), Vertical Gaze Nystagmus (VGN), Walk and Turn and One Leg Stand tests.  Next they perform three more evaluations:  Pupil Size Observation, Lack of Convergence and the Romberg Balance Test.  Written by Richard N. Blevins, visit my website.

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My Recent DUI Training in Field Sobriety Testing

February 10th, 2011 Richard Blevins Posted in Field Sobriety Tests No Comments »

Earlier this month, I had the pleasure of undergoing training to be certified in DUI detection and Field Sobreity Testing (FST) in accordance to the standards set out by the National Highway Traffic Safety Administration (NHTSA).  I had priously been certified by the State of Georgia in Standardized Field Sobriety Testing, while I was a police officer in DeKalb County, Georgia.  During the training, I learned how to administer the three standardized field sobriety tests, Horizontal Gaze Nystagmus test (HGN), the Walk and Turn test and the One Leg Stand test.  The HGN test looks for nystagmus in the eyes.  Nystagmus is the involuntary jerking of the eyes.  The officers are trained to look for 6 clues.  The clues are lack of smooth pursuit, distinct and sustained nystagmus at maximum deviation, and onset of nystagmus prior to 45 degrees.  If four clues are found, then NHTSA has conducted studies to show that it is 88% accurate that the person has a BAC over a .08.  On the second test, the walk and turn, the officer is looking for eight clues.  Two are in the instructional phase and six are in the walking stage.  They are: Starts too soon, unable to maintain balance, stops while walking, misses heel to toe, walks off line, raises arms, improper turn, and wrong number of steps.  If the officer observes two clues then NHTSA’s study shows it is 79% accurate that the person has a BAC of .08 or more.  The final standardized test is the one leg stand test.  Here, the officer is looking for four clues.  They are: Puts foot down, raises arms, hops, and sways.  If the officers observes two clues then NHTSA’s study shows it is 83% accurate that the person has a BAC of .08 or more.

Hiring the right attorney to look at the administration of the tests and other factors that could compromise the validity of each test is important in your DUI case.  If you are charged with DUI in Cobb County, Georgia or any surrounding county, please visit my website to discuss your case.

Written by Richard N. Blevins, Jr., former Cobb County State Court prosecutor, Assistant District Attorney in Cobb County, and former police officer.

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NHTSA’s Standardized Field Sobriety Tests

February 6th, 2011 Richard Blevins Posted in Field Sobriety Tests, Uncategorized No Comments »

The National Highway Traffic Safety Administration created three standardized field sobriety tests that law enforcement officers use in their DUI investigations.  They are the Horizontal Gaze Nystagmus test (HGN), Walk and Turn test, and the One leg stand test.  Officers are trained to look for a number of clues in each test.  In the HGN they are looking for 6 clues, in the walk and turn, they are looking for 8 clues and the one leg stand they are looking for 4 clues.  NHTSA conducted a study and it was shown that 88% of individuals who exhibit 4 or more clues in the HGN have a .08 or higher BAC (Blood Alcohol Content).  If 2 or more clues are found on the walk and turn test, 79% of the individuals have a .08 or higher BAC in the study.  If 2 or more clues are found on the one leg stand test, 83% of the individuals have a BAC of .08 or higher in the study.Hiring an experienced attorney to assist you in looking to see if these tests are administered correctly, could go along way in helping you with your DUI case.  Written by Richard N. Blevins visit me at my website or www.mariettacriminaldefense.com

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Facts About Field Sobriety Tests that NHTSA Does Not Publicize

August 5th, 2006 Allen Trapp Posted in Field Sobriety Tests 2 Comments »

  The three-test battery of Standardized Field Sobriety Tests has been promoted by NHTSA over the past twenty years and has been adopted by all fifty states.  In three highly publicized “validation studies” NHTSA claims to have found the proof  that these FST’s are valid measures of BAC.  All of the field studies are pretty consistent in terms of low false negative rates.  However, the same cannot be said of false positives, and that is what should concern us – the wrongly accused being arrested because of flawed “science.”

  The reason why so many people over .08 and.10 BAC show 4+ HGN clues is that so many people have 4+ HGN clues at .04, .05, and .06 BAC.  In the Good, Augsburger report, where 94% of .10 BAC were positive for HGN, 82% of the people UNDER .10 were also positive with at least 4 HGN clues.  Although NHTSA trumpted that the exercise is “94% accurate in identifying intoxicated people”, there was a concerted effort to ignore the fact that their own data says the test is 82% inaccurate as applied to INNOCENT PEOPLE. 

  The Colorado study found 1 in 8 people under .05 had 4+ HGN clues. 

  In the Florida study 16% of all people below .08 BAC had all 6 clues, and it suggests that over 50% had at least 4 clues, but it doesn’t just come out and say it.  NHTSA attempts to conceal these numbers by saying that half of the correctly released drivers had 0 or 2 HGN clues.  That suggests that HALF of the correctly released drivers (under .08) had MORE than 2 clues.  The Florida report also acknowledges that 67% of all incorrect arrests (under .08) had all 6 clues. 

  Too many judges (and certainly most prosecutors) have been sold on NHTSA’s cooked up numbers. NHTSA is an organization built on lies and deception, and one of the purposes of this blog is to educate the public about their deceptions.  In court we educate juries about how the government twists evidence and data in order to satisfy the NHTSA-MADD coalition with DUI convictions, regardless of the truth about any individual defendant.  After all, they’re just “drunk drivers” and not citizens in the eyes of the NHTSA-MADD coalition. 
Written by Allen Trapp who is board certified by the National College for DUI Defense and the author of Georgia DUI Survival Guide Visit Website

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HGN and Tharp’s Equation

August 5th, 2006 Allen Trapp Posted in Field Sobriety Tests No Comments »

Tharps Equation is used in the DRE (drug recognition expert) protocol to determine whether or not alcohol is the cause of the observed nystagmus. In another words, it “rules” out alcohol as the cause of impairment. The formula the DRE candidate is taught is BAC = 50 – A (Angle of Onset).

The interesting thing about Tharps Equation is that it is merely a statistical approximation – not a mathematical formula (and we all know what Mark Twain says about statistics). Tharps Equation can be off by .05% or more, even if the person has consumed no drug other than alcohol. Even its proponents concede that Tharp’s Equation does not reflect an exact relationship for all subjects at all times (according to NHTSA).

Keep in mind that the SFST protocol only allows for the prediction of above or below the per se level. What usually happens is the DRE talks and unqualified officers use the formula to estimate the BAC (although 99% of the time they are not performing the Onset of Nystagmus Prior to 45 Degrees properly). We question the “reliability” of a statistical formula, as well as the proper estimation of 45 degrees by the Officer.
Written by Allen Trapp who is board certified by the National College for DUI Defense and the author of Georgia DUI Survival Guide Visit Website

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