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The Evolution of the DRE Officer and Program

The Dark Ages

In the 1970s, prior to the establishment of the Drug Recognition Expert (DRE) Program, the following scenario was regularly played out on the streets of American communities:

While on routine patrol in city traffic in a marked police car, the watchful officer suddenly directs his attention to a specific car. Alerted perhaps by a traffic violation, such as speeding or an illegal left turn, or perhaps by erratic braking (not an actual breach of the law, but suspicious nonetheless), the officer activates the police car's emergency lights, and signals the car to stop. Both cars pull to the curb lane and stop.

The officer radios in his location to the police station, and slowly, yet attentively, walks up to the apprehensive and still-seated driver. The officer says firmly but politely, Good day, sir. May I see your driver's license and registration please." It's a demand, not a question.

As the nervous driver reaches for the glove box the officer asks, "By the way, what year is this car?" The driver stops reaching and replies, "It's a 93, no, 94 Ford. What's this all about officer?" The officer says, "I'll get to that in a moment. Remember? Your license and registration please."

The officer completes a mental checklist: bloodshot eyes, check, slurred words, check, forgetting about the driver's license, check, car smells like a brewery, check. "I think this guy might be deuce1," the officer thinks.

"Step out of the car, sir. I'd like you to do a few tests to see if you've had too much to drink."

During the "dark ages," roadside tests to determine if a person was under the influence of alcohol or drugs were not standardized. Through trial and error, each officer developed his or her own procedures in order to determine if the individual should be arrested for driving under the influence (DUI). Junior officers, modeling their superiors, would often add their own nuances to the procedures. These non-standardized roadside sobriety tests frequently included variations of counting and alphabet-recitation exercises2, coin pick-up tests3, and assorted balance and coordination tests.

Young officers quickly learned that the intoxicated person had difficulty remembering instructions, particularly more than one at the same time. In the above example, the officer demanded the driver's license and registration. As the suspect began to reach for these items, the officer asked another question - the year of the car. The driver had to be reminded to produce the license and registration. Without being aware of it, the officer was assessing the person's ability to divide his attention, that is, to do more than one thing at the same time.

Based on the totality of the investigation, including the individual's driving, the officer's general observations of the person's speech, appearance, demeanor, and the person's performance on the non-standardized roadside tests, the officer would make an arrest or release decision. If arrested, the driver would be taken to a police station, and would be advised of his rights and obligations under the implied consent law.4 Typically, the driver (now an "arrestee") would be administered an alcohol breath test. If the arrestee's alcohol concentration, as measured in breath, reached a certain statutory level, such as .10% BAC (blood alcohol concentration),5 the individual would be booked into the jail. The case would then be presented to the prosecuting attorney for review and prosecution.

During the 1960s and 1970s, many individuals were producing breath test results that were below the statutory level, even though they appeared to be inordinately impaired. Officers' options were both unsatisfactory and limited.

Releasing the person and requesting him or her not to drive was one option.6 A psychiatric evaluation of the driver was another option. In essence, the officer would suspect that the individual's erratic driving, behavior and appearance were related to a psychiatric disorder. A third option for handling the so-called "low blow" driver was to obtain an assessment for drug influence by medical personnel, such as doctors and nurses. (Los Angeles, as well as many other jurisdictions, have medical personnel on-duty throughout the day at larger jail facilities.) Unfortunately, then and now, many medical professionals receive limited formal training about the observable effects of abused drugs. And even if they have received formal training, actual experience in dealing with drug abusers in a non-traditional clinical setting may be limited.

More importantly, however, the medical professionals were assessing the arrestee at a different, sometimes significantly later, time. The person had been observed driving, was arrested, was taken to a police station and was given a breath test, all before being taken to an appropriate facility for a medical evaluation. The individual may no longer be under the influence of drugs at the time of the medical assessment. Simply, the drugs may have worn off.

Poly-drug (multiple drugs) use was another complicating factor. The poly-drug user, at different times, may exhibit nearly opposite drug effects. For example, at the time of the officer's encounter with an individual, the person may exhibit the behavior associated with stimulant use, such as aggressiveness, agitation, and dilated pupils. At the time of the medical evaluation, however, the same person may be sedated, lethargic, and sleepy, consistent with a narcotic analgesic such as heroin. The stimulant, cocaine, has worn off; heroin now dominates.

For these reasons and more, an evaluation by medical personnel was not a viable solution to the problem of identifying the drug-impaired driver.

In some cases, a blood or urine sample disclosed the presence of drugs in a suspected impaired driver. It was still difficult, nevertheless, if not impossible, to obtain a filing of charges in court, much less a conviction. Prosecutors were hampered by officers' limited abilities in articulating the basis of the opinion that the person was under the influence of drugs. A procedure was needed that officers could utilize in order to be able to detect, apprehend, assess, document, and subsequently prove in a court of law that the individual was under the influence of a drug. The Drug Recognition Expert (DRE) Program, procedures, and DRE-trained officer were the response to this recognized need.

Out of the Dark

Little has changed over the years from the above arrest scenario. The typical driving under the influence arrest begins with the officer's observations of driving, followed by the officer's face-to-face contact with the person. The major difference between the 1970s and the present is that officers now have a standardized method of assessing alcohol and drug-impairment at roadside: the Standardized Field Sobriety Test (SFST).

In the United States and parts of Canada, most police officers are taught the three phases of Driving Under the Influence (DUI)7 detection: (1) vehicle in motion, (2) personal contact, and (3) pre-arrest screening. Each of these phases requires decision making on the officer's part. In phase one, vehicle in motion, the officer's primary decision is whether or not to stop the vehicle. In phase two, the officer's primary decision is whether or not the driver should be instructed to exit the vehicle. The officer's primary decision in phase three is whether or not to arrest the person. The development, refinement, and validation of standardized procedures for phase three commenced at the same time that the need for procedures to detect the drug-impaired driver was growing. The resulting development of the SFST, which was largely through the efforts and research of Marcelline Burns, Ph.D. of the Southern California Research Institute (SCRI), was a critical step toward the development of DRE.8

Without repeating the extensive volumes of research conducted by Dr. Burns and her associates, the outcome was a standardized procedure that officers could use to determine at roadside if an individual was under the influence of alcohol. Dr. Burns evaluated the assortment of tests that officers through trial and error had developed throughout the United States and Europe. Three tests were found to be the most reliable predictor of a .10% BAC: horizontal gaze nystagmus (HGN) test, walk and turn test, and the one-leg stand test.9 When these tests were administered by a trained officer as a battery of examinations, officers could reliably determine if an individual's BAC was at or above the most common legal level at the time -- .10%.10

The SFST battery includes an assessment of an individual's ability to pay attention, follow simple instructions, and divide his or her attention.11 For example, during the walk-and-turn test, the suspect is instructed to stand on a real or imaginary line with one foot in front of the other. While the suspect stands in this position, the administering officer gives verbal instructions while at the same time demonstrating how the test is to be performed. Often, a suspect who is under the influence, will "forget" to maintain the initial position, and will either begin to perform the walking portion of the test before being told to do so, or will step out of the initial (instructional) position. During the walking or performance phase, the individual who is unable to divide his or her attention will frequently forget part of the instructions, such as counting out loud or touching heel to toe. With the support of the United States Department of Transportation, the battery of tests, known as the SFST, became the curriculum to train American officers in DUI detection.

Concurrently with the development of the SFST, drug abuse continued its steady incline. There was also a growing awareness by police officers, traffic safety researchers, prosecutors, and the general public, that drug-impaired drivers were significantly contributing to traffic injuries and fatalities. Police officers, seeing firsthand the carnage on the roads caused by drug abusers, were frustrated. They could arrest the drug-impaired driver, but were unable to obtain a conviction. Frustrated officers, problem-solvers by training and avocation, sought out solutions.

In particular, traffic enforcement officers from the Los Angeles Police Department (LAPD) began to develop their own expertise on the effects of impairing drugs other than alcohol. These officers consulted and worked with officers from LAPD's Narcotics Division.12 They consulted with doctors, psychologists, and drug abusers to educate themselves about the effects of drugs. In time, LAPD officers developed a step-by-step procedure that enabled them to determine drug influence.

These innovative LAPD officers did not "invent" new knowledge about the effects of drugs, as the effects of many drugs have been known for thousands of years. The writer Aldous Huxley has been quoted as saying that "Pharmacology antedated agriculture." Simply, this means that people were learning about the effects of drugs before they learned to plant and harvest crops. Probably through the observation of animals, humans very early on learned about the pharmacologic, mood and mind altering effects of certain drugs.

DRE Drug Categorization: Patterns of Signs and Symptoms

Borrowing extensively from medicine, psychiatry, physiology, toxicology, and associated fields, a drug categorization system was developed that placed the primary drugs of abuse into seven categories. These categories are not based on shared chemical structures, nor on their legality, or on the user's subjective experience. Rather, this categorization system is based on the premise that each drug within a category produces a pattern of effects, known as signs and symptoms. (A "sign" is detectable by an observer. Signs include bloodshot eyes, horizontal gaze nystagmus, pulse rate, impaired coordination, etc. A "symptom," on the other hand, is by nature subjective. It is experienced by the individual, and may be reported to the observer. For example, a feeling of nausea is a symptom. Hallucinations are symptoms, although they may elicit behavioral signs.) It is the pattern of effects, rather than a specific effect, that is unique to the category.

The LAPD officers borrowed extensively from existing bodies of knowledge to develop their drug categorization system. They also borrowed from the medical field to develop procedures to evaluate individuals for suspected drug influence. For example, it has been established for years that an individual's state of health, or intoxication for that matter, can be assessed by taking the person's vital signs ( blood pressure, pulse, and temperature in the case of the DRE). Likewise, the eye examinations,13 the balance and coordination tests, as well as other parts of a DRE evaluation have an historically accepted role in medicine. As one court stated in its decision regarding the scientific acceptance of DRE procedures, DRE is simply a compilation of the "tried and true."14

To summarize, the initial DREs used accepted medical techniques in order to detect the well-established effects of the drugs of abuse. What was new, however, was the development of a systematic and standardized step-by-step procedure that law enforcement officers could use to detect drug influence. This procedure began taking shape in the early 1980s.

A step-by-step checklist procedure is standard within law enforcement. Following a checklist ensures that nothing is left out, and aids in the presentation of evidence in court. Although the procedure was not nearly as standardized as it is today, these early DRE officers were increasingly called upon by prosecutors to testify about the effects of drugs on driving. Los Angeles judges began to routinely recognize the officers as experts, which meant that these officers could render opinions, unlike the non-expert who could only relate facts. Over a relatively short period of time, the rate of filing and subsequent conviction of drugged drivers equaled that of alcohol alone (approximately 95%).15

The testimony of DREs was usually not (and is still not) the only evidence that is introduced into court in DUI - drug cases. Usually, the prosecutor is able to present scientific evidence of use of drugs through urinalysis or blood analysis by toxicologists. A greater portion of the burden of proof that the individual was under the influence, however, was placed upon the observer of impairment, the DRE.

Laboratory and Field Evaluation of the DRE Program

The Drug Recognition Expert Program was becoming institutionalized within the LAPD and within Los Angeles courts in the early 1980s. The National Highway Traffic Safety Administration (NHTSA), an agency within the U.S. Department of Transportation, began to receive requests from various sources to study the validity and reliability of the DRE procedure. In response, NHTSA, in cooperation with the National Institute on Drug Abuse, undertook a laboratory evaluation of DRE procedures in 1984 at the Johns Hopkins University.16 Four LAPD DREs traveled to Johns Hopkins University. An experimental protocol was designed to test the accuracy of the DREs. Each of the officers was isolated, and independently conducted an assessment of 80 volunteer drug users. In a double-blind format, each of the volunteers had received either marijuana (2 dose levels), diazepam (2 dose levels), amphetamine ( 2 dose levels), secobarbital (1 dose level), or a placebo. Upon completing a 15 minute assessment, each of the officers was required to determine if the volunteer was impaired, and if so, the type of drug that was causing the observed impairment. The results of this study were reported as extremely encouraging to the DRE Program. In this controlled clinical study, DREs were over 90% accurate in determining impairment, and in correctly identifying the type of drug causing the impairment.17 The time had come to evaluate the DRE procedures in the law enforcement environment.

In 1985, NHTSA conducted a Field Validation Study of the LAPD DRE program. This study, which is also commonly known as the 173 Case Study, involved a much larger group of Los Angeles DREs, and involved individuals actually arrested for suspicion of driving under the influence of drugs. NHTSA contracted with a private toxicology laboratory to conduct blood analyses of samples obtained from the arrestees. The opinion of the DREs was then compared to the results of the laboratory's analyses for drugs. The results were very similar to the Johns Hopkins Study. Ninety-four percent of the time (162 suspects) a drug other than alcohol was found when the DREs said that the suspect was impaired by drugs. The drug determination was complicated by the fact that over 70% of the suspects yielded detectable levels of more than one drug. Overall the DREs were totally correct in their judgements on 49% of the suspects, i.e., all the drugs were identified, and partially correct, i.e., they identified at least one of the drugs in an additional 38% of the cases. They were wrong on only twenty-three subjects (13%) in that the correct drug category was not identified. Only in one case was no drug or alcohol found.

To summarize the findings as reported by NHTSA: 18

1. When the DREs claimed drugs other than alcohol were present, they were almost always detected in the blood (94%);
2. Multiple drug use was common: 72% used two or more drugs including alcohol. 45% used three or more drugs including alcohol;
3. All of the drugs were identified in almost 50% of the subjects;
4. 87% of the time the DREs correctly identified at least one drug other than alcohol;
5. Only 3.7% of the suspects who had used drugs had BACs equal to or greater than .10%.

It is likely that most, if not all, of the remainder would have been released to possibly drive again if the drug symptoms had not been recognized by the DREs.

The overall conclusion of the two studies was:

The LAPD drug recognition procedure provides the trained police officer with the ability to accurately recognize the symptoms of many types of drugs used by drivers.

Subsequent studies of the DRE protocol and program in other jurisdictions, particularly Arizona,19 supported the conclusions of the NHTSA studies.20

Curriculum Development and Institutionalization of the DRE Program

In the early to mid-1980s, the LAPD periodically conducted DRE training. There was no formal curriculum or course outline. Rather, the training included presentations by experienced police officers, narcotics detectives, physicians, and other technical experts. The training course, which varied in length between three and seven days, included a field certification stage. During this certification stage, candidate DREs were required to conduct DRE evaluations on actual suspects while under the supervision of an experienced DRE. Periodically, senior LAPD DREs would meet and decide as a group if the candidate was sufficiently proficient to be recognized as a DRE by the LAPD. Those that were recognized as proficient were deemed certified by the LAPD as a DRE. Out of need, standards for training and certification were slowly evolving.

In 1986, in recognition of the need to develop a formal curriculum, eighteen senior LAPD DREs were selected to develop and present the DRE curriculum. 21 A DRE school was conducted in May of 1986 in Los Angeles utilizing this initial cadre of instructors. NHTSA and other agencies monitored this school, with the goals of standardizing the curriculum, and developing a comprehensive curricula package for administrators, instructors, and students.22 In 1987, NHTSA completed the development of these lesson plans. NHTSA also conducted an instructor development school in Los Angeles to prepare DREs to present the curriculum. A successful DRE school was then held in Los Angeles using this new standardized curriculum.

The next step in the development and expansion of the DRE Program was the selection of four states to pilot the expansion of the program outside of Los Angeles. The states of New York, Arizona, Colorado, and Virginia were selected. These states were selected because they had in place aggressive DUI enforcement programs, including the training of officers in the SFST battery. Initially, officers from these jurisdictions traveled to Los Angeles to receive the classroom portion of DRE training. Upon completing the classroom training, Los Angeles DREs traveled to these other states to supervise field application and certification of these student DREs. After these students had attained certification as DREs,23 instructor schools were held to develop some of these new DREs as instructors. Subsequent DRE schools, conducted primarily by these new instructors, were then held in these additional states. This basic format of DRE expansion through the development of an initial cadre of DREs, followed by an instructor school, has continued to this day.

In the late 1980s, it was becoming clear to U.S. law enforcement and traffic safety officials that the DRE Program was poised for tremendous growth. Undoubtedly, for the DRE Program to expand, it needed administrative support and oversight on a national level. The International Association of Chiefs of Police (IACP) had for years maintained an ongoing relationship with NHTSA. The IACP supported NHTSA training programs for police officers, and advised NHTSA on research needs in traffic enforcement. The IACP was the logical organization to assume the oversight and administration of the growing DRE Program. In 1989, the IACP assumed this oversight, and became the certifying and regulating body for Drug Recognition Experts.

In 1988, the United States Congress passed the Omnibus Drug Bill. This legislation funded a large scale expansion of DRE training. Due in large measure to this bill, law enforcement agencies in 33 states have adopted the DRE program. As of 1998, there are approximately 4,000 certified DREs nationwide, including approximately 400 DRE instructors. In addition, DREs now serve in Canada, Australia, Sweden, and Norway. South Africa, through the auspices of its Council on Scientific and Industrial Research, is expected to adopt the DRE Program in the near future.

DRE training and certification records are now maintained by the IACP.24 NHTSA has maintained its role in the DRE Program by sponsoring curriculum update conferences, coordinating DRE courses nationwide, developing and issuing training materials, and generally providing administrative support of the DRE Program. The DRE Program is now formally titled the Drug Evaluation and Classification Program (DECP).

NHTSA Report to Congress on the DRE Program

In 1996, NHTSA evaluated its support of the development of the DECP in its report to the U.S. Congress.25 This report concluded:

"The Drug Evaluation and Classification Program has been remarkably successful in producing meaningful results...saving lives on our nation's roads...gaining court acceptance...and showing a steady return on investment. NHTSA's leadership role in development and implementation of the DECP produced scientific validation of the program, effective training and certification standards, and rapid expansion and institutionalization of the program. Taking into consideration the enormous cost to society of impaired driving injuries today, the economic impact of the DEC has more than compensated for the funds expended to implement and conduct the program. Added to this are the many lives that have been saved by DREs who identified medical crises in time to save the drivers. The Drug Evaluation and Classification Program has unquestionably produced profitable results which can be counted on for years to come."


1"Deuce" is a slang term, primarily used in California, for a person who drives under the influence of alcohol. "Deuce" is derived from 502, a former California penal code for DUI.

2A "counting" test may require the person to count backwards out loud from 38 to 11. In an "alphabet-recitation" test the individual may be instructed to recite the alphabet beginning with the letter G through X.

3In one type of "coin pick-up" test, the officer would place three coins of varying denominations on the road. The suspect would be instructed to pick up the coins in an order determined by the officer. For example, the officer might say: "Pick up the coins in the following order: quarter first, then the nickel, then the dime."

4Under the laws of most of the United States, an individual is considered to have given his or her consent to submit to a breath, blood or urine test subsequent to an arrest for driving under the influence. Driving is considered to be a privilege, and not a right. This is frequently termed "implied consent."

5In most of the United States, proscribed alcohol levels are defined as a weight of alcohol to volume of blood ratio. A .10% BAC is equivalent to 100 milligrams of alcohol per 100 milliliters of blood, or 100 milligrams of alcohol per 210 liters of breath.

6In many of the "release and request" dispositions, the individual had in fact ingested a relatively small amount of alcohol. Since the person was more impaired that would normally be expected, the officer would suspect that the person was simply an infrequent and intolerant drinker.

7Driving While Impaired (DWI), Driving While Abilities Impaired (DWAI), Operating Under the Influence (OUI) and DUI are for the most part synonymous terms. Terms vary according to jurisdiction.

8The National Highway Traffic Safety Administration sponsored two important studies that directly led to the development of the SFST battery, including specific procedures. Both studies were conducted by the Southern California Research Institute. They are: "Psychophysical Tests for DWI Arrest" (Final report, June, 1977), and "Development and Field Test of Psychophysical Tests for DWI Arrest" (Final report, March, 1981). A subsequent field evaluation of the SFST battery was conducted. This field evaluation, as reported in "Field Evaluation of a Behavioral Test Battery for DWI Report" (released September, 1983), by Anderson et al., supported the effectiveness of the SFST battery.

9Horizontal gaze nystagmus (HGN) refers to an involuntary side to side jerking of the eyes as they fixate and follow an object, such as a pen or pencil, that is moved horizontally in front of the person.

10In 1995, the Colorado Department of Transportation sponsored a field validation study of the SFST battery. This study documented the effectiveness of the battery at a .05 BAC. ("1995 Colorado SFST Field Validation Study" by Burns and Anderson).

11This important concept, termed divided attention, has direct association with the multiple tasks involved in operating a motor vehicle, during which many tasks are being done simultaneously.

Los Angeles Police Department officers Sergeant Richard Studdard (retired) and Detective Len Leeds (deceased) were largely responsible for the early development of DRE procedures.

13Horizontal gaze nystagmus, pupil size estimates, pupillary light reaction, and additional eye examinations are included in the DRE procedure.

14The People of the State of New York v. Mary Quinn, Defendant, Docket No. 3130122, District Court, Suffolk County, October 24, 1991, 580 N.Y. S. 2d 818, 153 Misc.2d 139 (N.Y.D.C. 1991).

Los Angeles City Attorneys Office, Hill Street Branch.

16The four LAPD officers who participated in this study as evaluators were: Sergeant Richard Studdard, Sergeant Jerry Powell, Officer Patricia Berry and Officer Doug Laird. All have since retired from the LAPD.

Identifying Types of Drug Intoxication: Laboratory Evaluation of a Subject Examination Procedure, May 1984 Final Report. George E. Bigelow, Ph.D. et al. Behavioral Pharmacology Research Unit, Department of Psychiatry and Behavioral Sciences. Funded by the U.S. Department of Transportation's NHTSA and the National Institute of Drug Abuse. (Commonly called the Johns Hopkins Study), NHTSA, Pub. No. DOT HS 806 753 (1985).

Field Evaluation of the Los Angeles Police Department Drug Detection Procedure. February, 1986, DOT HS 807 012, A NHTSA Technical Report, National Highway Traffic Safety Administration. Richard P. Compton. (Commonly referred to as the 173 Case Study).

19Drug Recognition Expert (DRE) Validation Study, Final Report to Governor's Office of Highway Safety, State of Arizona, June 4, 1994. Eugene V. Adler, Arizona Department of Public Safety and Marcelline Burns, Southern California Research Institute.

20Preusser, Ulmer and Preusser studied the impact of DRE training on alcohol-impaired driver arrests, finding that DRE-trained officers are more likely to arrest drivers with lower alcohol levels. Evaluation of the Impact of the Drug Evaluation and Classification Program on Enforcement and Adjudication, December, 1992. D.F. Preusser, R.G. Ulmer and C.W. Preusser. Report no. DOT HSA 808 058. (The DRE Program is also known as the Drug Evaluation and Classification Program (DECP)).

21The following Los Angeles Police Department officers were responsible for the development and presentation of the DRE curriculum: Patricia (Russell) Berry, James Brown, Milt Dodge, Ian Hall, Arthur Haversat, Clark John, Baron Laetzsch, Gary Lynch, Ron Moen, Michael Murray, Thomas Page, Craig Peters, Jerry Powell, Scott Sherman, Richard Studdard, Larry Voelker, Michael Widder, and Nicholas Zingo.

22John "Jack" Oates, William Nash, and Bill Tower (on loan to NHTSA from the Maryland State Police), represented NHTSA at this course.

23At this time, the Los Angeles Police Department was the certifying agency for DREs.

24The IACP also supports a DRE Section which serves as a resource and responds to the needs of DREs, program coordinators, and other traffic safety professionals. For information on membership requirements, the reader should contact the IACP at 1-800-THEIACP.

A Study of Working Partnerships: A Report to Congress on the Drug Evaluation and Classification Program. National Highway Traffic Safety Administration, April 1, 1996.