Archive for June, 2006

DUI “Eye Test” a Fraud?

Wednesday, June 28th, 2006

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.



Monday, June 26th, 2006

A couple of weeks ago I wrote in a post ("MADDness") that, deceptive statistics notwithstanding, two decades of MADD's more-jail-time model has not worked in dealing with the drunk driving problem. Challenged to offer a better approach, I followed up with "Time for a Change", emphasizing the need to stop throwing social drinkers in jail and focus instead on rehabilitation of the relative few causing most of the damage on the highways: alcoholic recidivists. The following editorial, written by a local judge, appeared yesterday in a Minnesota newspaper:

A new county jail: If we build it, they may not come

Once again the county commissioners are being asked to consider whether taxpayers should pay for a new jail.

We have all the prisons and jails we need; we just have to learn how to use them more wisely. And if we build a new one, we better be careful it fits in the 21st century, not the last. There are outside forces beyond our control that are already affecting Winona and the criminal justice systems across America….

The judge then listed a number of considerations, including:

The 'lock them up, build more jails' solution to crime has failed and run its course. Reason: We can't possibly catch and lock up all the bad people, and even if we could, we can no longer afford it. When some states pay more for incarceration than education, something's wrong.
A new principle is evolving: If we fear them, then we must lock them up to protect ourselves, not to change them ' we have more than enough prisons to house the dangerous. If offenders simply make us angry, and they will return to live among us, then we must find other ways to deal with them and to change their faulty belief systems and/or addictions that keep getting them in trouble with the law.
We've known for years that locking up offenders for rehabilitative purpose fails, in fact it often makes them worse. The National Institute of Corrections, U.S. Dept. of Justice concluded in 2000 that not a single study of official punishment found any consistent evidence of reduced recidivism. They found punishment increased criminal behavior by 0.07 percent.
DUI laws are now being challenged as failures. DUI laws are justified, but the way they are being implemented fails. DUI laws over-punish the social drinker (majority of Americans) and fail on the alcoholic high-risk multi-offender. The same National Institute of Corrections study found 'those under the influence of chemical substances' to be resistant to punishment. Yet our Minnesota laws require long-term mandatory jail sentences for repeat offenders, who are most likely alcoholics; needlessly filling our county jails. There is a reason many states are diverting repeat DUI cases to drug courts.

A Wisconsin study by its Department of Transportation (2004) found a third of the people convicted of DUI were repeat offenders; that those convicted of DUI drive 200 times for every time they get caught. They estimate 21,000 cars a day in Wisconsin are being driven by someone over the 0.08 BAC limit. That equates to about 18,000 a day for Minnesota. An impossible task for law enforcement.

My observations and opinions for what they're worth:

Courts of the future must change from what hasn't worked to what has shown to be more effective. Trials will remain the same, but upon conviction the prosecutor, defense attorney, correction staff and the judge will be obligated to find a 'problem-solving solution' to the offender's problem ' unless the offender poses a danger to society, then prison must be considered.
County jails will hold only people for trial and those considered dangerous or a flight risk. Jails will be used for short 'shock' time to enforce accountability. No longer will county jails be considered rehabilitative, thus freeing up cell space…

The dawning of reason.


“I Smelled a Strong Odor of Alcohol on the Suspect’s Breath”

Friday, June 23rd, 2006

You will never see a DUI case where the officer does not report an odor of alcohol on the suspect’s breath. Never. The officer expects to smell it and it is a psychological fact that we see, hear and smell what we expect to see, hear and smell. In fact, most police DUI reports are formatted for the usual symptoms: there will be a box for “odor of alcohol”, which the officer checks off. There are often three boxes, labelled “strong”, “moderate” and “weak”; there is no box for “none”, so that is not an option for the officer.  The ”strong” box is almost always checked.  Presumably, the stronger the odor of alcohol, the more intoxicated the person arrested.

There is only one problem with this:  alcohol in a beverage has no odor.

Assuming the officer actually does smell an odor on the breath, what he is smelling is not ethyl alcohol but the flavoring in the beverage. And the flavoring can be deceptive as to the strength or amount consumed. Beer and wine, for example, are the least intoxicating drinks but will cause the strongest odor. A much stronger drink, such as scotch, will have a weaker odor. And vodka leaves virtually no odor at all.

Consider a simple experiment. Have a friend drink a can of “near beer” — the stuff that looks, smells and tastes like beer but has no alcohol in it. Then smell his breath. You will smell an “odor of alcohol” — and maybe a strong one.

And, of course, there can be any number of causes of an “odor of alcohol” on a person’s breath: mouth wash, throat spray, cough syrup. Illness, indigestion or simple bad breath has been the cause of more than one officer’s trigger-quick conclusion that the suspect has an “odor of alcohol on his breath”.

The point of all this is that the odor of alcohol has very little relevence in a drunk driving case. It may or may not indicate that the person has consumed alcohol. It has absolutely no evidentiary value on the much more important question of how much the person has consumed — or what he had to drink, or when. Depending upon circumstances, a person with a single drink can have a “strong odor of alcohol on his breath”, and an extremely inebriated person can have a “weak” odor. And an experienced and honest DUI officer will readily admit this….if he is ever asked.

Unfortunately, evidence of the odor of alcohol on a person�s breath can have a significant impact on a DUI case. This is because most officers who pull a driver over for some driving irregularity at night are looking for further signs of drunk driving. When the officer approaches the driver’s window and smells alcohol, that confirms his suspicions. Since few can pass the “field sobriety tests”, particularly under the conditons in which they are given, an arrest is likely.

Are there any scientific studies to back up my claim that breath alcohol odor is largely irrelevant yet disproportionately weighted as “evidence” of intoxication?

In 1999, the same scientists whose federally-contracted studies became the basis of the so-called “standardized” battery of field sobriety tests conducted another study on the effectiveness of alcohol odor in detecting intoxication. These researchers used 20 experienced officers working with 14 subjects who were tested at blood-alcohol concentrations (BACs) ranging from zero to .13 percent. Over a four-hour period, the officers smelled the subject’s breath odor under optimal conditions, with the subjects hidden from view.

The conclusions of the study: Odor strength estimates were unrelated to BAC levels. In fact, estimates of BAC levels failed to rise above random guesses. Further, officers were unable to recognize whether the alcohol beverage was beer, wine, bourbon or vodka. According to the scientists, these results demonstrate that even under the best of conditions, breath odor detection is unreliable. Moscowittz, Burns & Furgeson, “Police Officers’ Detection of Breath Odors from Alcohol Ingestion”, 31(3) Accident Analysis and Prevention 175 (May 1999).


Breathalyzers: 40% Margin of Error is Acceptable Accuracy?

Tuesday, June 20th, 2006

With more than a little federal coercion, all states have now passed laws making it a criminal offense to drive with .08% alcohol in your blood. And most people suspected of violating that law are given breath tests to determine their blood-alcohol concentration (BAC).

The breathalyzer will take a small sample of the suspect’s breath and estimate how much alcohol is in it — and, then, estimate how much may be in the blood. And what that machine says is pretty much the end of it. There will be no second tests. There will be no cross-examination of the machine.

Are these machines so reliable and accurate that we have permitted them to become judge and jury and to determine guilt beyond a reasonable doubt?

Ignoring the many flaws of the machines for the moment (see “How Breathalyzers Work — and Why They Don’t”), scientists universally recognize an inherent error in breath analysis, generally of plus or minus .01%. That means that if everything is working perfectly (an unlikely scenario), a .13% breathalyzer test result can be anywhere from .12% to .14%. This has been acknowledged by courts across the country (see, for example, People v. Campos, 138 Cal.Rptr. 366 (California); Haynes v. Department of Public Safety, 865 P.2d 753 (Alaska); State v. Boehmer, 613 P.2d 916 (Hawaii), recognizing an even larger .0165% inherent error).

What does that tell us about the accuracy of these breathalyzers? Well, let’s take a common test result of .10%. Taking inherent error into consideration — and assuming the machine was working perfectly, the officer administers the test correctly, and the suspect’s physiology is normal and perfectly average — the true BAC could be anywhere from .09% to .11%. In other words, the true BAC can be 10% in either direction — or, put another way, anywhere within a 20% margin of error.

These machines have a 20% margin of error?

That’s right. A person accused of driving with over .08% BAC can be convicted by a machine whith a built-in 20% margin of error. Would you be comfortable with an airline pilot who worked with a 20% range of error? With a bank teller who gave you $90 cash for a $100 check? How about the sole evidence in a criminal case where guilt must be proven beyond a reasonable doubt?

But it gets worse. Most states have laws which establish standards for breath alcohol analysis. These set forth minimum levels of accuracy in a given test, usually determined by the requirement that two separate tests produce results within a given range. California’s requirements, for example, are fairly typical: to be admissible in court there must be two test results that are within .02% of one another.

What does that mean? Well, let’s again assume that you breathe into the machine and it produces a .10% reading. You are now required to breathe into the machine a second time. What test result would be necessary for the evidence to be considered acceptably accurate and legally admissible? .08? .09? 10? .11? .12? Actually, any of these readings would satisfy the .02% requirement: anything from .08% to .12% would render the test results “accurate”.

In other words, a 40% range of error in that second test is deemed sufficiently accurate to sustain the prosecution’s burden of proof “beyond a reasonable doubt”.

Close enough for government work…in a DUI case.


How You Breathe Affects Your Breathalyzer Results

Wednesday, June 14th, 2006

As I’ve indicated in numerous earlier posts, these breath machines which determine guilt or innocence in DUI cases are not exactly the reliable devices that law enforcement would have us believe.  Yet another example of that unreliability is the fact that the results will vary depending upon the breathing pattern of the person being tested.

This has been confirmed in a number of scientific studies. In one, for example, a group of men drank moderate doses of alcohol and their blood-alcohol levels were then measured by gas chromatographic analysis of their breath. The breathing techniques were then varied. The results indicated that holding your breath for 30 seconds before exhaling increased the blood-alcohol concentration (BAC) by 15.7%. Hyperventilating for 20 seconds immediately before the analyses of breath, on the other hand, decreased the blood-alcohol level by 10.6%. Keeping the mouth closed for five minutes and using shallow nasal breathing resulted in increasing the BAC by 7.3%, and testing after a slow, 20-second exhalation increased levels by 2%. “How Breathing Techniques Can Influence the Results of Breath-Alcohol Analyses”, 22(4) Medical Science and the Law 275. For another study with similar findings, see “Accurate Measurement of Blood Alcohol Concentration with Isothermal Breathing”, 51(1) Journal of Studies on Alcohol 6.

Dr. Michael Hlastala, Professor of Physiology, Biophysics and Medicine at the University of Washington, has gone farther and concluded:

By far, the most overlooked error in breath testing for alcohol is the pattern of breathing….The concentration of alcohol changes considerably during the breath…The first part of the breath, after discarding the dead space, has an alcohol concentration much lower than the equivalent BAC. Whereas, the last part of the breath has an alcohol concentration that is much higher than the equivalent BAC. The last part of the breath can be over 50% above the alcohol level….Thus, a breath tester reading of 0.14% taken from the last part of the breath may indicate that the blood level is only 0.09%. 9(6) The Champion 16 (1985).

Many police officers know this. They also know that if the machine contradicts their judgement that the person they arrested is intoxicated, they won’t look good. So when they tell the arrestee to blow into the machine’s mouthpiece, they’ll yell at him, “Keep breathing! Breathe harder! Harder!” As Professor Hlastala has found, this ensures that the breath captured by the machine will be from the bottom of the lungs, near the alveolar sacs, which will be richest in alcohol. With the higher alcohol concentration, the machine will give a higher — but inaccurate — reading.