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Signs of human narcotics abuse in K-9 vehicle stops

By Joe Keil

Most states recognize the term “free air space” — meaning a K-9 can sniff the exterior of a vehicle an officer has stopped as long as the sniff does not prolong the stop. A K-9’s ability to locate the odor of drugs is remarkable. A human being has approximately 5 million olfactory cells, whereas a German Shepherd has approximately 220 million olfactory cells. Given that superior ability, what reasons might a K-9 have for failing to alert or indicate on a stopped vehicle where the officer suspects narcotics?

Numerous variables exist, such as wind, temperature, humidity, and masking odors. When a K-9 fails to alert on a probable narcotics vehicle, several things can happen: the handler may become frustrated, the K-9 may become frustrated, the handler may believe the car did not contain narcotics, the officer who stopped the vehicle may believe the K-9 couldn’t find his own tail and won’t call for him again, or the handler could continue to ask himself, “What was in the vehicle, where was it, and why didn’t my K-9 alert?”

But what if the substances present were ones that K-9s are not trained to alert on, such as morning glory seeds, nutmeg, Salvia divinorum, Jimson weed, cold medicine, or the hundreds of other substances being abused? An understanding of the physiology of the human body and the symptoms of human drug use can be a key element in building reasonable suspicion to de-tain the operator or occupants of the vehicle. The result may be the opportunity to place an operator of a vehicle through the standardized field sobriety tests (SFSTs).

The Broad Spectrum of Narcotics
The human body has 11 major systems, all of which are affected by the abuse of drugs: they are the muscular, urinary, respiratory, digestive, endocrine, reproductive, skeletal, immune, nervous, circulatory, and integumentary systems. An officer’s ability to observe physiological signs and symptoms of drug use can be a crucial part in maximizing the K-9’s abilities on narcotic sniffs. If an officer can determine the category or types of drugs ingested, a huge advantage arises for the K-9 handler.

Seven categories of drugs make up the fundamental principle of the Drug Recognition Expert Program; the categories are based on the physiological effect each one has on the body. Drugs within the same category generally cause similar effects. Depressants, dissociative anesthetics, and inhalants all enhance horizontal gaze nystagmus (HGN), and usually do not affect pupil size. A few exceptions exist, such as the depressants Soma and Quaalude, which can cause pupil dilation. Dissociative anesthetics such as Robitussin or Coricidin Cough and Cold products containing dextromethorphan also can dilate the pupils if taken in high doses. Certain inhalants may dilate the pupils, as well. None of those narcotic categories contain drugs K-9s generally are trained to alert on. A person displaying HGN lowers your odds of a K-9 alert on a vehicle. However, keep in mind that individuals may be using multiple substances — some of which a K-9 is trained to indicate on.

How can we increase the odds of a K-9 alert? What if the subject displays dilated pupils? That increases our odds since the stimulant, hallucinogenic, and cannabis categories all contain drugs a K-9 is trained to alert on. Stimulants include drugs such as cocaine, base cocaine, methamphetamine, and methamphetamine base, which are all substances K-9s can hit on. However, keep in mind that drugs such as khat and prescription medications such as Ritalin and Adderall also fall within the stimulant category and K-9s are not trained to alert on those.

Hallucinogens include natural and synthetic drugs. Peyote, psilocybin mushrooms, nutmeg, and morning glory seeds are natural substances and K-9s are not trained to detect those odors. Ecstasy or methylendioxymethamphetamine (MDMA) — along with many of the designer drugs — contain methamphetamine which, again, K-9s are trained to alert on.

The cannabis category contains marijuana, hashish, hashish oil, and marinol: K-9s are trained to alert on three out of four of those odors.

Narcotics cause pupil constriction and include heroin, which is derived from opium and is a substance K-9s can detect. However, thousands of synthetic or semi-synthetic drugs in the narcotic category — such as Oxycodone, Fentanyl, Morphine, and Demerol — constrict the pupils, but are not drugs a K-9 is trained to alert on.

Building Reasonable Suspicion
An officer’s training and experience can increase his or her ability to build reasonable suspicion on a traffic stop to conduct an investigative detention. During the traffic stop, the physical signs a person displays can be a major piece of the puzzle when investigating criminal activity. Consider the following scenario: An officer stops a vehicle and is conducting SFSTs on the operator, who is extremely nervous. A K-9 unit arrives on the scene and the handler uses his partner to conduct an exterior sniff of the vehicle. The original officer noted three clues on HGN and one clue on the walk and turn. The K-9 does not alert on the vehicle and is returned to the squad car. The handler then walks around the vehicle while the officer is still conducting SFSTs. Upon looking into the vehicle, he observes in plain view numerous blister packs on the floor and a box of Coricidin Cough and Cold HBP. Is drug use occurring? Yes. Even though the substance is legal, if you are impaired, you can still be arrested; yet, that is not a drug the K-9 is trained to alert on.

In another example, during a traffic stop you notice that the operator has bloodshot, glassy eyes. You observe a bottle of Visine and tube of Carmex on the seat next to him. As he speaks, the subject continually licks the inside of his mouth and appears to have a dry mouth. You take the subject’s pulse, which is 140 beats per minute. Now the odds of a K-9 alert have substantially increased. As a result of the officer’s training and experience, it is reasonable to believe that the subject was smoking marijuana.

Effects of Multiple Drug Use
Not all narcotics users consume only one type of drug. What happens to their bodies when they consume drugs from more than one category? Four different effects can occur. The first is the Null Effect: when two drugs are consumed and neither has a specific effect, then no effect will be observed. I know that may sound confusing, but let’s think of a drug that does not dilate the pupils. Some examples would be depressants, inhalants, and dissociative anesthetics. Because most drugs in those categories will not dilate the pupils, combining them will not result in dilated pupils.

Second is the Additive Effect, which occurs when one drug causes a specific effect and another drug taken in combination also causes or enhances the same effect. Now think of a drug that dilates the pupils: hallucinogens, stimulants, or marijuana. Each of those substances dilates pupils, so when taken in combination, they will cause the pupils to become extremely dilated.

Third is the Overlapping Effect, which occurs when two drugs are taken in combination and one drug causes an effect but the other drug does not cause that effect. For example, a stimulant, hallucinogen, or marijuana dilates the pupils and depressants, inhalants, or dissociative anesthetics do not affect pupil size. When a drug that dilates pupils is taken in conjunction with a drug that does not affect pupil size, the cumulative effect is dilated pupils.

Finally, we have the Antagonistic Effect, which occurs when one drug causes a specific effect and a second drug causes the opposite effect. For example, when someone combines drugs that dilate the pupils — such as stimulants, hallucinogens, or marijuana — with a drug that constricts the pupils — such as narcotic analgesics — it is unknown what the pupil size would be. Pupil size could be dilated, normal, or constricted depending on the quantity of drugs ingested and how much time had passed before you observed the person’s eyes. Remember, the eyes work in tandem, so if one eye is affected by drugs, the other also will be affected. If one pupil is extremely large and the other is extremely small, you are not encountering a combination of drugs, but rather a medical condition.

Deadly Combinations
We have discussed and given examples of how combining drugs affects pupil size. Now let’s look at how other body systems could be affected. What would happen if someone took a narcotic in combination with a depressant — a common combination? Both drug categories lower pulse rate and blood pressure and act like sedatives, so respiration will decrease and the individual could slip into a coma. If a person ingested cocaine and ketamine, one is a stimulant and the other is a dissociative anesthetic, yet both will elevate pulse, blood pressure, and body temperature, increasing the risk of cardiac arrest.

Don’t think that combining only illegal drugs can be deadly. Consider a person who consumes various legal substances from within the same category. For example, a person drinks Red Bull in combination with ingesting Sudafed — both of which are stimulants. That combination will cause an additive effect, and the person will appear hyperactive, be unable to sit still, and their pulse, blood pressure, and body temperature all will elevate to an unknown level. Again, the risk of cardiac arrest is increased, yet those are both legal substances.

Understanding the physiology of how drugs affect the human body can change the course of a traffic stop and increase the odds of a K-9 alert. That understanding is not 100 percent effective, because we know that some people may be transporting drugs they are not using, plus certain prescription medications and over-the-counter drugs can mimic the effects of illegal drugs.

Just Say No
Obviously, much more information is available on this subject. To increase your effectiveness as a K-9 handler, you can learn more about which drugs are being abused, current drug trends, and how drugs affect the body. I recently published a book entitled When Just Say No Doesn’t Work. This book is a comprehensive guide for officers, parents, teachers, and medical professionals to help them recognize and identify drug use. The book is available at www.

A hands-on, two-day course also is available for officers, K-9 handlers, and their K-9 partners. The course is designed to train officers to recognize both uncontrolled and con-trolled substances during traffic stops. For more information, e-mail operationrush@hotmail.com.

Joe Keil is a 20-year veteran of law enforcement and is currently assigned to the patrol division. He became a K-9 handler in 1997. Keil has extensive training through the Drug Evaluation and Classification Program sponsored by the National Highway Traffic Safety Administration, certifying him as a Drug Recognition Expert.

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