Causation or correlation?

So here I am heading home from the office the other day listening to All Things Considered on the radio and there's this story about Kenya trying to fight the scourge of HIV by encouraging men to get circumcised. The reporter quoted a scientific study that the rate of HIV infection in uncircumcised men was substantially higher that the rate for men who were circumcised.

Well, that got me to thinking. This link between circumcision and HIV infection rates - is it an example of causation or correlation?

In other words, does getting circumcised reduce one's risk of getting infected by HIV, or is there something else at work? Is it because uncircumcised men have riskier sex practices? Is it because circumcised men are practicing safer sex?

The literature appears to be all over the place. Of course since the World Health Organization (WHO) jumped on board the circumcision train money has poured into Africa to fund circumcision programs. But there is still precious little hard evidence that circumcision has anything to do with HIV prevention.

Adding to my skepticism that there is no causal relation between the two are activists in Europe and the United States attempting to ban the procedure on newborns. If circumcision really prevented HIV infections, why would anyone be campaigning against it?

Now I'm no doctor and I am not going to sit here and pretend that I have some vast store of knowledge about the transmission of infectious disease or the human reproductive system. But I do think this issue is a perfect example of the causation v. correlation puzzle we run into in the courtroom.

The police coordination exercises the police use on the roadside to determine whether they're going to arrest a motorist for driving while intoxicated have everything to do with correlation, not causation. The studies used to provide a modicum of "scientific heft" to the roadside exercises all speak of correlations between levels of intoxication and performance on the exercises. Not one of them show evidence of causation.

The distinction is important. Let's say you're watching your favorite team play in a crucial game (sport and team not important). All season long whenever you've worn a certain shirt or cap or drank a certain beer or ate a certain sandwich, your team came through. Your actions did not cause your team to prevail. There was no causal link between your shirt (or your cap or beer or sandwich) and your team's performance. There was just a correlation - when you wore your shirt, your team just happened to win.

On the other hand, if it's dark out when you're driving home you turn on your headlights - as does everyone else out on the road. The lack of light caused you to turn on your headlights. There is a causal connection between nighttime driving and headlight use.

We can draw correlations between all sorts of statistics but just because you can draw a correlation between two observations doesn't mean that one caused the other. Your lucky socks won't help you win that poker game tonight, but your skill in reading the other players and their cards will.

Just because a motorist exhibits certain clues or signs or behaviors when walking up and down a straight line, doesn't mean that alcohol caused his performance. There are plenty of other factors that are not taken into account by the officer asking you to perform the exercise. And while the so-called validation studies may have drawn correlations to intoxication and performance on the roadside exercises, the studies did not make any causal connections.

The prosecutor will try to make it look like there is a causal connection between intoxication and performance, it's your job to point out to the jury the difference between causation and correlation.

Television show DUI perpetuates the lie

I finally got around to watching an episode of TLC's new reality show DUI the other night. For those of y'all not familiar with the show, it follows the stories of two people arrested for driving under the influence - from traffic stop to the end of the case.

The first episode introduced us to Cierra and Jimmy, two folks unfortunate enough to find themselves cuffed and stuffed into the the back seat of a police car. Cierra was accused of drinking and driving while Jimmy was accused of driving while high on the hippy lettuce.

Of course we had to ride along with police officers out looking for drunk drivers. Up in Oklahoma it appears that sobriety checkpoints are okey-dokey (so much for the 4th Amendment north of the Red River). A long line of cars sat on the shoulder of a highway in Tulsa as officers approached each car.

Following Cierra we live the nightmare of being arrested and carted off to jail. Answering questions asked by a hostile police officer. The humiliation of being searched and photographed. Calling her mom to get bailed out.

The show ends with both Cierra and Jimmy pleading out their cases - on what appeared to be their first court date. No questioning the legality of the stop. No questioning the validity of the roadside coordination exercises. No challenging any of the evidence. Just walking up, pleading guilty and walking away.

I guess that's the message the cops and producers want to send out - if you're arrested, you must be guilty. We even have both of our stars confessing before the camera.

Jimmy was excited because he got an 18-month deferral, meaning the case would be dismissed if he completed his probation and he could keep it off his record. Of course, since Jimmy was dumb enough to sign the release there is no undoing his arrest and conviction.

Somehow I doubt we'll be getting too many folks on DUI walking out with dismissal forms. A 30-minute time frame with two cases doesn't give much time to discuss much of substance. We'll get to hear each week from an officer telling us that DWI is the worst possible offense a person can commit. We'll see people acting contrite and telling us how the experience changed their lives. But we won't see anyone challenging the evidence. We won't see anyone fighting their case. We won't see anyone who was convicted on the opinion testimony of a police officer. We certainly won't see anyone being acquitted by a jury.

DUI is propaganda. Its purpose is to pound the notion that if someone's arrested they must be guilty into the skulls of its viewers. The goal is to poison the jury pool across the country.

What we really need is a show in which we see officers lying on the witness stand. A show in which we see officers making questionable arrest decisions. A show in which we see the shortcomings of the state's breath test machine. A show in which we see how the Constitution has been subverted in the name of making our streets safer. But that'll never sell.

The eyes have it?

The American Optometric Association adopted a resolution at their 2011 House of Delegates endorsing the use of the Horizontal Gaze Nystagmus test by "properly trained and certified" police officers. The AOA "found" that the test is a scientifically proven reliable indicator of intoxication.

The AOA also said it supports the use of optometrists as consultants for law enforcement in the area of the HGN test.

Of course let's not forget the distinction between optometrists and ophthalmologists. An optometrist is must have a Doctor of Optometry degree. An optometrist serves as the primary provider for normal vision problems and for yearly eye exams. An ophthalmologist, on the other hand, is a medical doctor who specializes in the eyes. An ophthalmologist is able to diagnose complicated eye issues and is able to perform laser eye surgery.

You go to the optometrist to get fitted for glasses or contacts. You go to the ophthalmologist when you've got a problem with your eyes. Just who do you think is more qualified to opine on the validity of an HGN test?

But the optometrists believe that training a police officer with no knowledge of the physiology of the eye or of common eye ailments for a couple of hours is sufficient to make that officer an "expert" in the determination, by use of a pseudo-scientific eye test, of whether a motorist has lost the normal use of his or her mental or physical faculties. More than that, the optometrists apparently believe that a two-hour training session on HGN makes a police officer just as qualified as an optometrist to testify as an expert on HGN.

AOA Resolution 1901

You don't suppose that the AOA was just looking for a way to provide supplemental income for its members as whores for law enforcement, do you?

Legislature to consider new drunk driving offense

Last month I wrote about Austin Police Chief Art Acevedo's brilliant scheme to put more motorists under the thumb of the criminal (in)justice system. I also pointed out the intellectual dishonesty behind the proposed driving while ability impaired offense. But, come January, the Texas Legislature will consider creating the criminal offense of driving while ability impaired.

"When people are arrested for an alcohol-related offense, it needs to show up on their record," said Austin PD Commander of Highway Enforcement Jason Dusterhoft. "Our No. 1 goal is to keep drunk drivers off the road and keep them from killing people. DWAI would be a way for us to work toward eliminating repeat offenders.

No, Mr. Dusterhoft, I must disagree. If the motorist did not commit an offense, then the arrest shouldn't show on their record. Mr. Dusterhoft apparently believes that the police are never wrong when it comes to arresting motorists for allegedly driving drunk.

If you read the NHTSA training manual you will find that if a motorist exhibits four or more "clues" on the pen-and-eye test there is an almost 80% chance that the motorist has an alcohol concentration of .08 or higher. Of course that means that almost 20% of the time the voodoo test is wrong.

NHTSA claims the walk and turn exercise is accurate in predicting an alcohol concentration of .08 or higher 68% of the time and that the one leg stand gets it right 65% of the time. By my math, that means the coordination exercises are wrong about one time in three.

But here's the rub for folks like Mr. Acevedo and Mr. Dusterhoft; what happens if an officer arrests a motorist based on his performance of the roadside coordination exercises and the motorists proceeds to blow less than .08 on the breath test machine?

Might it mean that the officer was wrong in arresting the motorist? Might it mean that NHTSA's coordination exercises aren't accurate predictors of one's alcohol concentration?

On Cowboys and DUI's

Once again a Cowboy makes the headlines for running afoul of the law. This time, however, it's one of them Cowboys from up in Stillwater.

Justin Blackmon, a 20-year old wide receiver for Oklahoma State, was arrested Monday night for driving under the influence (DUI) in Dallas after Monday Night Football. Of course, if you're a Dallas fan, heavy drinking is about the only way to handle one of their games.

When Mr. Blackmon was stopped for speeding, the officer administered a series of roadside coordination exercises. Presumably this was after he smelled alcohol on Mr. Blackmon's breath. Even though Mr. Blackmon "passed" the exercises he was still arrested for DUI because (1) he was under the age of 21 and (2) he had a detectable amount of alcohol in his body.

There is no allegation that Mr. Blackmon was intoxicated or otherwise impaired. The only allegation is that he consumed alcohol and got behind the wheel of a car. Since driving under the influence is a Class C misdemeanor (the equivalent of a traffic ticket), the maximum punishment Mr. Blackmon could face is a $500 and the suspension of his driving privileges for 60 days.

So before anyone gets too up in arms over Mr. Blackmon's arrest, what he allegedly did Monday night in Dallas is nothing worse than most college students do every weekend.

Austin police chief wants new DWI charge

Art Acevedo, the police chief in Austin, Texas, has gone on the record in favor of creating a new DWI offense in Texas. Mr. Acevedo would like to add the offense of driving while ability impaired (DWAI) for motorists who are below the legal limit.

In Mr. Acevedo's world, any driver with an alcohol concentration of greater than .05 but less than .08 would be charged with the new offense. I guess that would do away with that pesky little matter of a driver blowing under the limit - and a jury wondering why he's on trial.

No one has proposed what category misdemeanor the new offense would be. My guess is it would be a Class C misdemeanor - the equivalent of a traffic ticket. It would make no sense to create a new Class B drunk driving offense. Would DWAI become the new "reduced charge" for those accused of DWI?

The proposed offense makes no sense on an intellectual level. If a motorist is stopped and the officer suspects he is intoxicated, the officer will administer roadside coordination exercises. If the motorist "fails" those exercises, he would be arrested for DWI and asked to blow into the breath test machine. At what point would an officer decide to arrest for DWAI? According to the NHTSA Manual, the roadside coordination exercises are designed to detect drivers with an alcohol concentration of .08 or higher; does this mean that officers will arrest drivers who "pass" the roadside exercises? If the person "fails" the roadside exercises an officer could not arrest for DWAI, because that person would have lost the normal use of their mental or physical faculties according to NHTSA - at that point it wouldn't matter what the driver's alcohol concentration was.

And, where's the scientific evidence that a motorist's faculties are impaired to the point of being a danger at an alcohol concentration of .05? There are people driving completely sober that are a hazard on the road.

The addition of a new DWI offense will do nothing more than pull more people into the reaches of the criminal (in)justice system.

Plea bargains in DWI cases? Are you serious?

Yes, Virginia, the Harris County DA's Office does offer plea bargains on DWI cases -- even felony DWI cases. Last week KPRC-TV ran a story about plea agreements in felony DWI cases in Harris County -- like it was something out of the ordinary. I hate to be the one to break it to MADD, but there have been plea bargains since the day Cain stoned Abel.

I don't know the exact percentage of cases at 1201 Franklin in which a person accused of a crime pleads guilty, or no contest, in exchange for a reduced charge or reduced sentence; but when I was in law school we were told that upwards of 90% of all cases are resolved without a trial -- that means plead out or dismissed.

Most DWI prosecutions are based solely on the arresting officer's opinion -- not on any scientific grounds. If there is no breath or blood test then it comes down to whether the officer thinks the motorist is intoxicated based on his observations of the motorist or the motorist's performance on police coordination exercises. In those cases the video is often the determining factor in the jury's deliberations: if he looks drunk he'll be convicted, if he doesn't, he'll be acquitted.

Most prosecutors believe that it's better to get the conviction regardless of the sentence. That conviction can then be used down the road to enhance an offense should a motorist be hauled back into court. Of course some of those prior convictions aren't nearly as good as prosecutors thought they were at the time. There are quite a few that can't be used for enhancement purposes because of the language used on the judgments when the accused entered his or her plea. Then there are the thousands of cases involving convicted felon Dee Wallace, the disgraced former technical supervisor who filed false maintenance records for the breath test machines under her control.

It doesn't surprise me, though, that this story ran less than two weeks prior to the Fourth of July weekend -- fanning the flames surrounding the Bill of Rights as we head toward another No Refusal weekend.

New roadside sobriety tests in Louisiana?

Here's a little bit of humor for y'all on this Memorial Day weekend. Lord knows I need a laugh after seeing that "No Refusal Weekend" has made a return to the horror of the 4th Amendment.

Thanks to my dad for sending this over to me (I made a few changes to the narrative, though)...

A Louisiana state trooper pulled a car over on Interstate 10 just west of Lake Charles. When the trooper asked the driver why he was speeding, the driver said he was a magician and juggler and was on his way to Baton Rouge to do a show with the Shrine Circus and he didn't want to be late.

The trooper told the driver he was fascinated by juggling and asked if the driver would do a little juggling for him and then he wouldn't give him a ticket.

The juggler told the trooper he had sent his equipment ahead and didn't have anything to juggle. The trooper said he had some flares in his trunk and asked if he could juggle them. The juggler said he could, so the trooper got the five flares, lit them and handed them to the juggler.

While the man was juggling, a car pulled in behind the patrol car. A drunken good ol' boy from a neighboring parish got out, watched the performance and then went over to the patrol car, opened the rear door and got in.

The trooper observed the man and went over to his patrol car, opened the door and asked the drunk what he was doing.

The drunk replied, "You might as well take me to jail, 'cuz there ain't no way I can pass that test."

Roadblocks down in the bayou

The Sheriff over in Cameron Parish, Louisiana decided to set himself up a roadblock to catch all those pesky drunk drivers in Grand Lake last Friday night. His posse was made possible by a $330,000. The sheriff's office spent about $80,000 for equipment and overtime expense for that li'l ol' roadblock.

"The citizens are glad that we're taking a proactive approach to making sure the highways are safer." Chief Deputy Ron Johnson, CPSO

And what a success it was. Of the 589 vehicles stopped without either reasonable suspicion or probable cause, deputies made all of six arrests. Of those arrests, only two were for driving while intoxicated. Deputies administered coordination exercises to nine motorists -- I would assume because they smelled the devil's drink on their breath.

Listening to the newscast you would think the reporter is the spokesperson for the sheriff's office.

Seeing might just be believing

Earlier this month, police in Clarence, NY pulled over Michael Bartz for driving 59 mph in a 45 mph zone. That Mr. Bartz was speeding wasn't newsworthy. Blowing a .30 on the state's breath test machine, on the other hand, was.

The newspaper article states that a 160 lb. man would have to consume 11 alcoholic drinks in an hour to reach a .30. My Alcopro Drink Wheel tells me that it would take 13 drinks to achieve that blood alcohol concentration. Either way, that's a lot of alcohol in a short amount of time.

According to the Phoenix House's "Facts on Tap" website, these are the effects and behaviors you would expect to see at various blood alcohol concentrations:

BAL .02%-.03%: You feel mildly relaxed and maybe a little lightheaded. Your inhibitions are slightly loosened, and whatever mood you were in before you started drinking may be mildly intensified.

BAL .05%-.06%: You feel warm and relaxed. If you're the shy type when you're sober, you lose your feelings of shyness. Your behavior may become exaggerated, making you talk louder or faster or act bolder than usual. Emotions are intensified, so your good moods are better and your bad moods are worse. You may also feel a mild sense of euphoria.

BAL .08%-.09%: You believe you're functioning better than you actually are. At this level, you may start to slur your speech. Your sense of balance is probably off, and your motor skills are starting to become impaired. Your ability to see and hear clearly is diminished. Your judgment is being affected, so it's difficult for you to decide whether or not to continue drinking. Your ability to evaluate sexual situations is impaired. Students may jokingly refer to this state of mind as beer goggles,but this BAL can have serious repercussions. See the pages on Sex and Alcohol: A Risky Relationship for how to protect yourself.

BAL .10%-.12%: At this level, you feel euphoric, but you lack coordination and balance. Your motor skills are markedly impaired, as are your judgment and memory. You probably don't remember how many drinks you've had. Your emotions are exaggerated, and some people become loud, aggressive, or belligerent. If you're a guy, you may have trouble getting an erection when your BAL is this high.

BAL .14%-.17%: Your euphoric feelings may give way to unpleasant feelings. You have difficulty talking, walking, or even standing. Your judgment and perception are severely impaired. You may become more aggressive, and there is an increased risk of accidentally injuring yourself or others. This is the point when you may experience a blackout.

BAL .20%: You feel confused, dazed, or otherwise disoriented. You need help to stand up or walk. If you hurt yourself at this point, you probably won't realize it because you won't feel pain. If you are aware you've injured yourself, chances are you won't do anything about it. At this point you may experience nausea and/or start vomiting (keep in mind that for some people, a lower blood alcohol level than .20% may cause vomiting). Your gag reflex is impaired, so you could choke if you do throw up. Since blackouts are likely at this level, you may not remember any of this.

BAL .25%: All mental, physical, and sensory functions are severely impaired. You're emotionally numb. There's an increased risk of asphyxiation from choking on vomit and of seriously injuring yourself by falling or other accidents.

BAL .30%: You're in a stupor. You have little comprehension of where you are. You may suddenly pass out at this point and be difficult to awaken. (But don't kid yourself: Passing out can also occur at lower BALs. But, at lower blood alcohol levels, you may decide You've had enough to drink and go "pass out." With an alarming BAL like .30%, your body will be deciding to pass out for you.) In February 1996, an 18-year-old student died of alcohol poisoning with a BAL of .31% after attending two parties the night before.

So, according to research conducted by the Phoenix House, Mr. Bartz should not have been able to operate a motor vehicle at that blood alcohol concentration. Could the state's breath test machine have been wrong? Did Mr. Bartz' blood alcohol concentration increase after he was stopped? If he had been drinking while driving, did the alcohol in his mouth affect the test result?

Dr. Kurt Dubowski, considered by many to be an expert in the field of alcohol testing, put together this chart showing the effects of alcohol on the body at various concentrations:

BAC (g/100 ml of blood or g/210 l of breath)	Stage	Clinical symptoms
0.01 - 0.05	Subclinical	Behavior nearly normal by ordinary observation
0.03 - 0.12	Euphoria	Mild euphoria, sociability, talkitiveness Increased self-confidence; decreased inhibitions Diminution of attention, judgment and control Beginning of sensory-motor impairment Loss of efficiency in finer performance tests
0.09 - 0.25	Excitement	Emotional instability; loss of critical judgment Impairment of perception, memory and comprehension Decreased sensitory response; increased reaction time Reduced visual acuity; peripheral vision and glare recovery Sensory-motor incoordination; impaired balance Drowsiness
0.18 - 0.30	Confusion	Disorientation, mental confusion; dizziness Exaggerated emotional states Disturbances of vision and of perception of color, form, motion and dimensions Increased pain threshold Increased muscular incoordination; staggering gait; slurred speech Apathy, lethargy
0.25 - 0.40	Stupor	General inertia; approaching loss of motor functions Markedly decreased response to stimuli Marked muscular incoordination; inability to stand or walk Vomiting; incontinence Impaired consciousness; sleep or stupor
0.35 - 0.50	Coma	Complete unconsciousness Depressed or abolished reflexes Subnormal body temperature Incontinence Impairment of circulation and respiration Possible death
0.45 +	Death	Death from respiratory arrest

The National Highway Traffic Safety Administration (NHTSA) includes a chart entitled "Common Signs of Alcohol Influence" is its DWI Detection and Standardized Field Sobriety Testing training manual -- the book that most law enforcement agencies use to train their officers in the administration and evaluation of police coordination exercises.

Here are the effects and behaviors at various blood alcohol concentrations per NHTSA:

.03 Slowed reactions

.05 Increased risk taking

.08 Impaired vision

.10 Poor coordination

Once again there are questions about the accuracy of Mr. Bartz' breath test. While the article notes that Mr. Bartz failed the coordination exercises administered by the police (that's a big surprise), it also states that officers found nothing out of the ordinary until they conducted the breath test.

A high breath test may be grounds for some attorneys to recommend an immediate plea because they see no way to win the case. It can also be an opportunity to turn the state's evidence and witnesses against the state and use them to your advantage.

What should I do if I'm pulled over for DWI?

I'm often asked what someone should do if they're pulled over on a DWI. Now the first thing to remember is that unless you are in an area with bars and restaurants, a DWI stop rarely starts out as a DWI stop.

Typically a driver is stopped because of a traffic or equipment violation. Depending on the location and time of day, the officer may or may not start off with the assumption the driver has been drinking.

The first thing you want to do is get your driver's license and insurance card out before the officer approaches your window. If you show the slightest difficulty in getting them out after he asks for them, he will note that you fumbled for your license when he writes his report.

You always want to be polite. Always remember that it is the officer who is going to decide whether or not to make this a DWI stop. If you are rude and combative, believe me, that will make it into the officer's report as a sign of intoxication.

Generally if the officer asks you to get out of your car you are going to be arrested whether you perform any of his coordination exercises or not. Do not lean against your car after getting out. If you do, the officer will indicate this as another sign of intoxication.

Listen carefully to the officer's questions and, if you choose to answer them, only answer what is asked. If you've been drinking, your breath will have the odor of an alcoholic beverage; remember this if the officer asks if you've been drinking.

Before you agree to perform the officer's coordination exercises you need to realize that every question the officer asks you and every task he asks you to perform are designed to gather evidence that will be used against you.

If you were stopped for speeding or for an equipment violation you need to be aware that neither of these is an indicator of impairment. Even if the officer notes you had the odor of an alcoholic beverage on your breath, slurred speech and bloodshot eyes, without any signs of impairment, the officer cannot establish probable cause to arrest you (though you will be arrested).

If you are familiar with the coordination exercises the officer will ask you to perform and you know what "clues" he's looking for then you may decide to perform them -- although I would counsel against it. Just remember, even though there are 93 components to the walk-and-turn test, for instance, the officer (and prosecutor) will claim you are intoxicated if you exhibit 2 or more "clues."

If you were not involved in an accident and you don't have a child in your car and the local police are not running a "No Refusal" weekend, do not blow into the breath test machine. I repeat - do not blow into the breath test machine. If you blow over .08, you've got problems, if you blow under .08 the officer will find some reason to explain the score -- maybe you "elmininated" the alcohol from your system or maybe you were also doing either prescription or illegal drugs that "synergized" with the alcohol and caused impairment.

If you are subject to a mandatory blood draw if you refuse the breath test you sit on the horns of a dilemma. If you think you have an alcohol concentration of less than .08 then you probably should blow into the machine. Otherwise you will be looking at a blood test. While a jury is trained to think of blood tests as infallible, there are a number of evidentiary issues that can keep a blood test out of evidence, or at least cast serious doubt on its accuracy.

Using the HGN test to your advantage

"I am going to check your eyes. Keep your head still and follow this stimulus with your eyes only. Keep following the stimulus with your eyes until I tell you to stop."

So begins the administration of the horizontal gaze nystagmus (HGN) test to the suspected drunk driver. The officer then begins the magical process of waving a pen back and forth in front of the driver's eyes to determine if he or she consumed any alcohol. Nevermind that, by that point, the driver has usually admitted to drinking "a couple" of beers or mixed drinks.

But instead of looking for signs of impairment, let's look for some signs that our driver is not impaired. Did the driver keep his or her head still? Did the driver follow the movement of the pen with his or her eyes? Was the driver standing still?

In order for the officer to administer the "test" correctly, he must be able to look into the driver's eyes. In order for him to look into the driver's eyes, the driver must be standing still and not swaying. The stance the driver takes during this test is the most normal stance he or she will take during the administration of the standardized field sobriety tests (or, as I prefer to call them, the police coordination exercises).

In order to "take" the pen and eye test, the driver must exhibit some fine motor skills. He or she must stand still and, without moving his or her head, follow an object being passed in front of the eyes. The driver must also understand the directions he or she was given by the officer - a test of mental faculties.

Think about it, if the driver can't stand still, can't keep his head still, can't follow the pen with his eyes and can't follow directions, the officer can't complete the test.

Therefore, the very fact that the officer completed the administration of the HGN test demonstrates that the driver still had the use of his or her mental and physical faculties.

Passing before our eyes

I find it a bit ironic that the most "scientifically valid" standardized field sobriety test is also the one that jurors are the least concerned about. I am, of course talking about the horizontal gaze nystagmus (HGN) test.

At trial the prosecutor and arresting officer will do their little "dog and pony show" about how the driver's jerky eyes indicates that he must be intoxicated. The officer will testify (usually) that he found all six clues when administering the test and that the only logical conclusion is that the driver was intoxicated at the time he was driving.

Of course if you take out a stop watch while viewing the video it becomes evidence quite quickly that the officer didn't administer the test correctly. Either he moved the pen too quickly or too slowly in front of the driver's eyes or he held the pen too high or too low when making the passes.

Do you file a pretrial motion to suppress the test, file a motion in limine requesting the opportunity to take the officer on voir dire before he testifies about the HGN test, do you conduct a vigorous cross examination of the officer on his mistakes or do you gloss over the test and move on to other topics?

Here's a little hint...in most jurisdictions when the jury watches the video all they see is your client standing still with the officer waving a pen in front of your client's face. The jurors don't see your client's eyes jerking. In fact, you can often score points with the jury by asking the officer if your client stood still, didn't sway and didn't move his head back and forth.

Jurors are far more concerned with how your client did on the Walk and Turn and One Leg Stand tests because that's when they get to see if your client "looks drunk." Those are the tests to attack hard and often.

I tend to ask a few questions about the "pen and eye test" and then move on to more fertile ground -- unless the officer butchered the test to such a degree that it casts his entire investigation into question.

The eyes have it

Arresting officers in DWI cases love to get on the stand and announce that your client exhibited all six "clues" in the horizontal gaze nystagmus (HGN) test and, as a result, it was a foregone conclusion that your client was intoxicated.

But wait just a second - even though this "test" is couched in scientific terms, the follow-the-pen show on the video is far from being either scientific or valid.

Nystagmus is defined by NHTSA as "an involuntary jerking of the eyes." NHTSA states that alcohol causes horizontal gaze nystagmus.

The American Academy of Opthamology defines the condition as "is an unintentional jittery movement of the eyes" that "usually involves both eyes and is usually exaggerated by looking in a particular direction."

So, for your police officer trained to diagnose eye conditions by another police officer, nystagmus is an indicator of intoxication. To a trained medical practitioner, however, nystagmus is a medical condition.

When an officer detects "nystagmus" someone is likely to be placed under arrest and hand-cuffed. When a trained medical practitioner detects nystagmus, on the other hand, he is going to conduct a thorough evaluation and will more than likely call in another specialist to examine the patient.

When an officer conducts the pen-and-eye test in the field, there are no controls for the effects of weather, lighting or traffic conditions. The officer must estimate the time for each pass of the pen and the distance the pen travels to the side. When a trained medical practitioner conducts an eye test to determine if nystagmus is present, the test is performed in a controlled environment with medical instruments by a doctor who went to medical school.

Finally, when an officer detects "nystagmus," he is looking for evidence to confirm his suspicion that the motorist is intoxicated. When a trained medical practitioner detects nystagmus, his job is to eliminate all possible causes until he can diagnose the underlying cause.

The scientific literature indicates a myriad of conditions responsible for nystagmus - from epilepsy to Parkinson's disease and from muscular dysfunction to head trauma. But, according to the police officer's diagnosis, the only cause for nystagmus of a driver being tested at the side of the road is alcohol consumption.

Statistical reasoning

I came across an interesting article in Cognitive Daily this afternoon about reasoning with statistics. The article described three studies conducted to determine how well people understood statistics and observable data.

In the first study people were asked which hospital would be more likely to have a day in which 60% of the babies born were boys: a hospital with 15 births a day or a hospital with 45 births a day. Most of the respondents said the percentages should be the same; very few respondents understood that the smaller a test sample, the more likely there are to be large variations day to day.

In another study respondents were asked to imagine they were on a remote South Pacific island and that they discovered a new species of bird as well as an obese native. The respondents were then asked to estimate the portion of the new bird species that were blue and the portion of the native population that was obese. Most respondents believed that the blue bird was very representative of the new species, regardless of whether they saw one blue bird, three blue birds or twenty of them. They also believed that one obese native was not necessarily representative of all natives, but, the more obese natives they observed, the higher percentage they attached to them.

The final study looked at a high school senior trying to decide where to go to college: Ivy College or Liberal College. Our senior had friends at both schools. His friends at Ivy had many complaints about the college, the atmosphere, the social scene, etc. His friends at Liberal were very content. He then went on a visit of both schools: he loved Ivy but was not so hot about Liberal afterwards.

A vast majority (74%) of the respondents said he should go to Ivy based on his friends' comments and his visit.

Researchers then ran a second test using the same scenario: only this time our senior made a list of classes, sites and activities from both colleges and picked several at random before making his visit. Once this detail was added the number of respondents picking Ivy dropped to 56%. The researchers concluded that when the respondents were told about the list they decided to look at the problem from more of a statistical viewpoint -- his friends at the schools had a better sampling of the environment than he did on his one visit.

The lesson to be learned is that the sample size will affect the reliability of the statistics generated from it. So, when confronted with statistical evidence, from DNA samples to field sobriety tests to breath-alcohol tests, focus on the sample size. The larger the sample size, the more reliable the numbers generated.

On field sobriety testing, point out the relative small sample sizes used in the "validation studies." Look at everything from the location of the tests, the ages and sexes of the participants, the level of intoxication of participants in lab testing, the time of day and the number of officers who took part in the study.  

As far as the breath test result -- just how accurate do you really think two breath samples taken two minutes apart are? 

Officers administer field sobriety tests incorrectly 97% of the time

Recently Lance Platt, a certified NHTSA SFST practitioner, instructor and trainer, published a paper in the DWI Journal: Law & Science that examined the differences between the manner in which officer are trained to perform field sobriety tests and the manner in which they actually administer them.

For the Horizontal Gaze Nystagmus test, Mr. Platt recognized 16 elements that make up the test. After examining 360 recorded evaluations, he found only 24 were performed correctly per the NHTSA Manual. Those 24 represent only 7% of the tests administered, meaning that officers administered the test incorrectly 93% of the time.

HGN Test Elements

• Place feet together
  
• Place hands to your sides
  
• Maintain the position
  
• Look at the stimulus
  
• Follow the stimulus with your eyes only
  
• Do not move your head
  
• Continue to follow the stimulus until the test is complete
  
• Do you understand?
  
• Officer positions stimulus correctly
  
• Officer checks for equal tracking
  
• Officer checks for equal pupil size
  
• Lack of smoot pursuit (timing element)
  
• Distinct & sustained nystagmus at maximum deviation (timing element)
  
• Onset of nystagmus prior to 45 degrees (timing element)
  
• Vertical gaze nystagmus
  
• Possible optokinetic (environmental issue)
  

For the Walk and Turn test, Mr. Platt recognized 21 elements that make up the test. Of the 360 recorded evaluations, he found that only 67 were administered correctly per NHTSA. In other words, officers administered the test incorrectly 81% of the time.

Walk and Turn Elements

• Imagine a line
  
• Place your left foot on the line
  
• Place your right foot in front of your left
  
• Touch the heel of your right foot to the toe of your left
  
• Keep you arms to your sides
  
• Remain in this position and do not start walking until told
  
• Do you understand?
  
• Take nine heel-to-toe steps up the line
  
• Turn by leaving the lead foot on the line and taking a series of small steps
  
• Take nine heel-to-toe steps back down the line
  
• Officer demonstrates walking phse
  
• Officer demonstrates turn
  
• Look at your feet
  
• Count your steps out loud
  
• Keep arms at your side while walking
  
• Do not stop walking
  
• Do you understand?
  
• Begin walking and count your first step forward from the heel-to-toe position as step number one
  
• Poor testing surface
  
• Issues with shoes
  
• Weather
  

For the One Leg Stand test, Mr. Platt recognized 16 elements that make up the test. Of the 360 recorded evaluations, he found that officers administered the test correctly only 50% of the time.

One Leg Stand Elements

• Place feet together side by side
  
• Keep your arms to your sides
  
• Remain in this position and do not start until told
  
• Do you understand?
  
• Keep both legs straight
  
• Keep your arms by your sides
  
• Lift the leg of your choice
  
• Approximately 6 inches off the ground
  
• Point the toe of the elevated foot parallel to the ground
  
• Look down at the raised foot
  
• Count out loud by 1000's until told to stop
  
• Do you understand?
  
• Officer demonstrates balance and counting
  
• Poor testing surface
  
• Issues with shoes
  
• Weather

When he evaluated in how many of the 360 test sequences all three tests were administered correctly, he found that only occurred ten (10) times, meaning that officers administered at least one test wrong 97% of the time.

Unfortunately in Texas judges routinely hold that the incorrect administration of these tests goes to the weight, not the admissibility, of the evidence. This despite the warning in the NHTSA Manual that "if any of the standardized field sobriety test elements is changed, the validity is compromised."

Into the belly of the beast

Here's a link to Richard Alpert's DWI Case Law on the Texas District and County Attorneys Association website.

I found two cases summaries to be quite interesting as they relate to an officer's developing probable cause to arrest a motorist for driving while intoxicated.

Maxwell v. State, 253 S.W.3d 309 (Tex.App.—Fort Worth, 2008, pet. ref’d).

Officer may consider defendant’s refusal to do Field Sobriety Tests when determining the issue of probable cause to arrest.

Texas Dept. Of Public Safety v. Nielsen, 102 S.W. 3d 313 (Tex.App.—Beaumont, 2003, no pet.).

Substantial evidence existed of probable cause for driver’s arrest for driving while intoxicated (DWI) where police officer noticed several signs of intoxication including alcoholic odor coming from vehicle, driver’s refusal to make eye contact with officer, driver’s refusal to roll down window, driver’s response that he had consumed two to four beers when asked if he had been drinking, and driver’s refusal to take field sobriety tests. The totality of the circumstances is substantial evidence of probable cause for Nielsen’s arrest.

These cases seem to say that an officer may arrest a motorist for DWI absent field sobriety tests when that arrest decision is made after the motorist declined to perform the tests. Thus questioning an officer about when he made up his mind that he had probable cause to arrest a motorist for DWI becomes very important in determining if there was, indeed, probable cause for the arrest.

Based on these cases, the odor of an alcoholic beverage by itself, or in conjunction with bloodshot eyes or slurred speech, don't give rise to probable cause to arrest for DWI absent more evidence of intoxication.

Implied consent: a one-act drama

Somewhere in Texas at a Department of Public Safety driver's license office...

CLERK: Next.

APPLICANT: I'm here to get a driver's license.

CLERK: Let me see the paperwork.

APPLICANT: Here you go (handing application to the clerk).

CLERK: Now I need you to stand perfectly still while I wave this pen in front of your face. Just a second while I turn on the camera.

APPLICANT: (looks puzzled)

CLERK: Hold that head perfectly still. Here we go (waving a pen back and forth in front of applicant's face). Okay, that was good. Now I need for you to stand on one leg with your arms at your side. Whatever you do, don't put your foot down.

APPLICANT: (looks very puzzled while she struggles to keep from falling over). Can I ask you what this is all about?

CLERK: You can ask, but I can't answer that question just yet. Now I need for you to walk heel-to-toe up and back along that black line with your arms at your side. Take nine steps each way, please.

APPLICANT: You've got to be kidding.

CLERK: Do I look like I'm kidding (glaring at applicant in that way only a civil servant can)? Walk up and back along that line. Now!

APPLICANT: (with resignation) Fine. Here I go.

After the applicant finishes walking along the line she walks back up to the counter.

CLERK: Now you need to pay the fee and sign this form and then you'll be a legally licensed driver in Texas.

APPLICANT: (looking at a blank piece of paper with a signature blank) There's nothing on this paper. What am I signing?

CLERK: Do you want your license or not? You need to pay the fee and sign that piece of paper. We haven't got all day.

APPLICANT: (looking down at her watch stops herself from commenting) Here's your money. Do you have a pen?

CLERK: (looking incredibly put upon) Here.

The applicant signs the blank paper and hands it back, along with the pen, to the clerk.

APPLICANT: What was that paper all about? Was that just for my signature on my license?

CLERK: No. That paper was a waiver of your constitutional rights to remain silent and or speak to an attorney. You also waived your protection from self-incrimination and unreasonable search and seizure. Finally, and most importantly, you are now guilty until proven innocent. Have a good day. Next!

APPLICANT: (looking very disturbed) Wait just a minute. What are you talking about? What do you mean I waived my constitutional rights and protections?

CLERK: Well, anytime a police officer gets it into his head that you might be driving while intoxicated - you know, smells alcohol on your breath, for instance, you agree to blow into the state's breath test machine - but don't ask anyone how it works. If you ignore your obligation to provide evidence against yourself then we'll take your license away from you for 6 months and make you beg a judge to let you drive your car. Oh, and if the officer decides to arrest you and you, if you didn't blow into the machine, that's an indication that you were driving while intoxicated. Here's your license. Next!

APPLICANT: (looking down at her license in complete disbelief) What the...?

A little professional courtesy?

State District Judge Elizabeth Berry scored a victory in Johnson County (Texas), when the trial court ruled that blood samples taken after she was arrested for driving while intoxicated are inadmissible due to a defective warrant.

The affidavit said that after Judge Berry was stopped for driving 92 miles per hour, on Interstate-35W, officers saw eight beer bottles in the car.

The affidavit didn't say where the beer bottles were in the vehicle, if they were open or if they were hot or cold.  It did however state that Judge Berry refused sobriety tests and appeared confused and unstable, but didn't describe how the officer came to that conclusion.

The official paperwork also said that Judge Berry was, "unusually quiet due to intoxicated state."  When the affidavit was faxed to a local judge it was sent back, saying more detailed information was needed for a warrant to be issued.

After the arresting officer added that his partner said Judge Berry had the smell of an alcoholic beverage on her police were given approval to draw blood.

After reviewing all the information Thursday it was ruled that there was not enough evidence to give permission to draw blood, so the blood samples and intoxication levels are inadmissible in court.

The trial court's decision illuminates what is and what isn't probable cause to obtain a "blood" warrant in a DWI arrest.  I think it also points out that there is insufficient cause to arrest a citizen on suspicion of DWI based on a traffic violation (not noted as a "reliable indicator" of intoxication), the smell of an alcoholic beverage, the presence of alcohol in the car and a refusal to perform police coordination exercises. 

This decision provides further fuel to my advice to decline a police officer's "invitation" to perform coordination exercises at the scene and to refuse to blow into the state's breath test machine.