Category Archives: Field Sobriety Tests

Court Rejects Field Sobriety Test

The most critical evidence in a drunk driving case, after the blood or breath test, is the battery of field sobriety tests administered roadside by the officer before deciding whether to arrest.  These ”tests” are designed in theory to determine any impairment which may affect the safe operation of a vehicle. 

In fact, field sobriety tests (FSTs) simply test the physical skills and experience of the subject; a physically fit officer who has performed them hundreds of times will perform far better than an elderly, overweight, injured or unathletic person who is completely unfamiliar with the tests.  Add to this that the suspect is nervous and/or scared,  is attempting them in the dark late at night, in front of a police car with flashing lights, on a sloped roadside, with cars whizzing by within a few feet, possibly on high heels….Well, you get the picture.    

As I’ve mentioned in past posts, these “tests” are unreliable and highly inaccurate (see Field Sobriety Tests: Designed for Failure? and Are Field Sobriety Tests Valid?).  And this has been clearly demonstrated in scientific research. 

In 1991, Dr. Spurgeon Cole of Clemson University conducted a study on the accuracy of FSTs. His staff videotaped individuals performing six common field sobriety tests, then showed the tapes to 14 police officers and asked them to decide whether the suspects had “had too much to drink and drive”. Unknown to the officers, the blood-alcohol concentration of each of the 21 DUI subjects was .00% — stone sober. The results: the officers gave their opinion that 46% of these innocent people were too drunk to drive! In other words, the field sobriety tests were hardly more accurate at detecting intoxication than flipping a coin. Cole and Nowaczyk, “Field Sobriety Tests: Are they Designed for Failure?”, 79 Perceptual and Motor Skills Journal 99 (1994).

A common reply from police and prosecutors to these criticisms is that one of the FSTs is not affected by any of these considerations:  horizontal gaze nystagmus (HGN).  Basically, this test involves the officer observing and estimating measurements of a suspect’s eyeball movements.  However, the test was never designed for detecting driving impairment nor for determining actual blood-alcohol levels, nor is the officer remotely qualified to administer this opthamological test — and certainly not under roadside conditions.  (See my earlier posts, Nystagmus: the “Eye Test”,  Nystagmus: The ‘Eye Test’ (part 2), Nystagmus: The ‘Eye Test’ (part 3), and DUI ‘Eye Test’ a Fraud?)

Years ago, when HGN was first introduced by police agencies around the country, the courts refused to admit the results into evidence — on the grounds there was no scientific accceptance of the test for determining alcohol impairment.  Gradually, however, and with considerable political pressure from prosecutors and MADD, local courts gradually began admitting HGN into evidence.  And the seemingly scientific nature of the test proved to be very impressive to juries.

Recenly, the Illinois Supreme Court considered whether HGN should continue to be admitted into evidence.  Two days ago they filed their decision:  No — not without a hearing where the prosecution must prove that the test is scientifically accepted.  Illinois v. McKown (Docket No. 102373, filed September 20, 2007).


(Thanks to Illinois attorney Donald J. Ramsell.)

DUI Cop Refuses Breath Test

I posted a few days ago about an Illinois judge who refused to cooperate with officers investigating him for felony DUI, refusing to submit to field sobriety and breath tests. The hypocrisy applies to law enforcement as well:

Officer Honored for DUI Arrests Charged in

Alcohol-Related Crash

Pekin, Ill. Dec. 13. AP – An off-duty central Illinois police officer honored two years ago for cracking down on drunken driving has been charged in an alcohol-related crash that injured 10 people… (Greg)

Heiken, honored by the Illinois Department of Transportation’s traffic safety division in 2004 for making the most DUI arrests in Woodford County, faces up to three years in prison and could lose his job if convicted of the felony aggravated DUI charge…

Heiken admitted drinking at the Par-A-Dice, but refused blood-alcohol testing, according to the affidavit. Blood was taken against his wishes because people were injured in the accident, but test results were not available.

Funny how judges and cops have one righteous standard for the public, quite another for themselves.

What’s the Right Way to Give Field Sobriety Tests?

In most DUI investigations, the main evidence in determining whether there is probable cause to arrest is a battery of "field sobriety tests". Of course, if the officer administers the test incorrectly (as is commonly the case), the results are invalid — and an innocent person may be arrested.

So what is the correct way to give the tests and interpret them?

It's all laid out online (pdf) in the 165-page DWI Detection and Standardized Field Sobriety Testing Student Manual (2004 edition), published by the National Highway Traffic Safety Administration (USDOT) and widely used for training by law enforcement agencies nationwide. Read it and understand why few officers do it right.

(Thanks to Doug Hazelton.)

DUI “Eye Test” a Fraud?

The critical part of any pre-arrest investigation is the administration of the “field sobriety tests” (FSTs). These usually consist of a battery of excercises involving balance, coordination and mental agility — and are difficult to perform for even a sober person under ideal conditions (see “Field Sobriety Tests: Designed for Failure?”). Although there are many different tests (finger-to-nose, alphabet, etc.), an increasing number of law enforcement agencies are requiring their officers to use only the federally-recommended battery of three “standardized” FSTs.

The most recently developed of these is horizontal gaze nystagmus (HGN), commonly known as the “eye test”. It is particularly effective in trial not because of its accuracy, but rather because it appears to jurors as scientific in nature. As I have indicated in previous posts, however, HGN as a test for intoxication is fundamentally flawed and rarely understood or properly administered by police officers. (See “Nystagmus: The Eye Test”, “Nystagmus: The Eye Test (Part 2)”, and “Nystagmus: The Eye Test (Part 3)”.)

A study (Booker, 144(3) Science and Justice 133-139, 2004), has reviewed the scientific validity of the nystagmus test:

The Horizontal Gaze Nystagmus (HGN) test was conceived, developed and promulgated as a simple procedure for the determination of the blood alcohol concentration of drivers suspected of driving while intoxicated (DWI). Bypassing the usual scientific review process and touted through the good offices of the federal agency responsible for traffic safety, it was rushed into use as a law enforcement procedure, and was soon adopted and protected from scientific criticism by courts throughout the United States. In fact, research findings, training manuals and other relevant documents were often held as secrets by the state. Still, the protective certification of its practitioners and the immunity afforded by judicial notice failed to silence all the critics of this deeply flawed procedure….

In 1998 the integrity of the statistical evaluation of the original research upon which the validity of the tests rested was unfavorably reviewed [5]. In 2001 new research indicated that the Horizontal Gaze Nystagmus (HGN), the cornerstone of the test battery was fundamentally flawed and that the HGN test was improperly conducted by more than 95% of the police officers who used it to examine drivers suspected of driving while intoxicated (DWI) [6]. This summary critique demonstrates that it is scientifically meretricious and that the United States Department of Transportation indulged in deliberate fraud in order to mislead the law enforcement and legal communities into believing the test was scientifically meritorious and overvaluing its worth in the context of criminal evidence….

Deliberate fraud. Pretty strong language for a scholarly journal. After reviewing the flawed and deceptive justifications for using nystagmus in DUI investigations, the authors concluded that the test was essentially without scientific validity:

The state’s argument for the field sobriety tests does not rest on proof of merit, but upon qui tacet consentit reasoning ‘ that those tests have been so widely accepted they must have been subjected to some kind of review prior to adoption in the many jurisdictions where they are used, that somewhere along the way someone would have spotted the flaws and shortcomings. Considering that the student manual was originally considered to be a confidential state document and was only obtained through an ‘Open Records Act’ request, silence from the scientific community cannot be considered an endorsement of the program.

Are “Field Sobriety Tests” Valid?

Has the media finally stopped buying into the propaganda from MADD and begun independently investigating the truth? Following a recent story in the Washington Post critical of Washington DC’s "zero tolerance" laws, now comes another another Post story openly questioning the validity of "field sobriety tests" — a validity which I’ve repeatedly challenged on this blog (see, for example, "Field Sobriety Tests: Designed for Failure").

DUI Hokeypokey

Police, Lawyers And Scientists Engage in a Clumsy Dance Over the Merits Of Roadside Sobriety Tests

November 15. Stand up! Heels together. Toes out. Hands at your sides. Raise the leg of your choice right in front of you, six inches off the ground, leg straight, toe pointed. Keep your eyes on your raised toe and begin counting aloud from 1,001 until I say stop. Do you understand? Begin. One thousand one. One thousand two . . Keep going

Some dark night on the side of the road, police lights flashing in your peripheral vision, your freedom may depend on how well you do this. Did you sway? Raise your arms for balance? How about hop? Or put your foot down? If you did any two, a police officer will conclude with 65 percent accuracy, as stipulated in the prevailing science of inebriation diagnostics, that you may be too drunk to drive.

And if you bent your leg, stared straight ahead instead of at your foot or began before I said so, you may be in trouble. Police officers are taught that people under the influence of alcohol don’t follow directions well. If you made it through 30 seconds ramrod straight, congratulations! You may not be drunk. This is the one-leg stand — OLS in cop-speak. It is one of the three scientifically researched standardized field sobriety tests, blessed by the National Highway Traffic Safety Administration, that officers call "the holy grail" and give on the side of the road to help them decide whether to make a drunk driving arrest….

The one-leg stand has its skeptics and its court challenges, and plenty of them, but, according to NHTSA, the test is "easily performed by most unimpaired people." Oh, really? On a recent sunny afternoon in Dupont Circle, Franklin Urena, 32, a waiter at Chevy’s, couldn’t do it. "I have flat feet," he explained as he started hopping at the count of 1,021. His friend, Henry Van Dyke, 50, didn’t make it past the count of 1,003. "Maybe if I had a glass of wine I could do better because I wouldn’t be so self-conscious," he said. "I have no coordination."

Christine Ju, Elisa Catalano and Justin Sullivan, all in their early thirties, balanced well but didn’t follow directions. "What an absurd test," sniffed Catalano, a yoga teacher. In a completely unscientific test of 14 random people, five passed, seven failed and two were judgment calls — one because he counted quickly in Italian and the other because it was unclear whether her wobbles would count as a sway….

So hundreds of thousands of drivers have been arrested — no doubt many deservedly so — on the basis of a 30-year-old study [by Marcelline Burns] that, critics argue, has never been published in a peer-reviewed, scientific journal, never tested on a large scale with a control group and, perhaps more astonishing, has nothing to do with actual impairment from alcohol…..

Some forensic psychologists and, understandably, a slew of DWI defense attorneys have been assiduously picking apart Burns’s research on the standardized field sobriety tests for years….Troll the Internet, and you will quickly find disparaging reports with titles like "Field Sobriety Tests: Designed for Failure"…. But she is unmoved. "We’re now 30 years past the development of the test. They’re widely used by police officers. Why would they use them if they don’t help them make a proper decision?" she said. "These defense attorneys write all this stuff, but never once do they suggest an optional test. What do they want the officer to do? Toss a coin?"

Not at all, says Spurgeon Cole, a forensic scientist and consultant in Georgia who has been her chief nemesis in court and expert witness for the defense for years. But maybe videotapes in patrol cars, he argues, would help remove some of the subjectivity. "We have no idea how well a sober person can perform on the SFST [field tests]. How does age or gender affect performance? How does fatigue or practice affect performance?" he has written. "Without answers to these basic questions, the SFST remain in the same category as tarot cards."

Cole did his own study, administering the tests to 21 of his students at Clemson University in South Carolina — none of whom had had a drop of alcohol — and then showing the videotape of their performance to a group of officers. They officers reported they’d arrest nearly half the students. "And these people had absolutely zero to drink," Cole said in an interview. "These tests are absolutely worthless."

(Thanks to George Bianchi of Seattle.)