Drug Recognition Expert Overview
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The Drug Recognition Expert Program: An Overview


The Drug Recognition Expert (DRE) Program and procedures were initially developed in the 1970=s by traffic enforcement officers of the Los Angeles Police Department (LAPD).  This program trains selected police officers to utilize a step-by-step evaluation procedure, that enables the officer to determine whether an individual is under the influence of drugs, and then to determine the type of drug causing the observable impairment.  Importantly, the procedure enables the DRE to rule in (or out) many medical conditions, such as illness or injury, that may be contributing to the impairment.  Although the primary focus of the DRE procedure is driving under the influence (DUI) enforcement, the procedures have been applied to Health and Safety Code violations, probation, parole, drugs in the workplace issues, and other areas where accurately identifying the drug-impaired individual is relevant. 


The accuracy of the procedure used by DREs has been validated in two controlled studies.  In 1984, a research study at Johns Hopkins University showed that Los Angeles DREs were able to accurately distinguish between the drug-impaired and non-drug-impaired individual.  A subsequent Field Validation Study (173 case study) sponsored by the National Highway Traffic Safety Administration in 1985 evaluated the accuracy of the DRE procedures in actual arrest situations.  Again, the DREs were very successful in identifying both the drug-impaired individual and the class(es) of drug(s) causing the impairment.  Subsequent studies of the DRE protocol and program in other jurisdictions, particularly Arizona, supported the conclusions of these initial studies.


The success of these studies has precipitated the dissemination of DRE techniques to over 40 states plus the District of Columbia.  In addition, officers in Canada, Australia, Norway, Germany and Sweden have been successful in adapting DRE skills to their jurisdictions. 

The DRE procedures have been subject to numerous defense motions challenging the admissibility of DRE testimony.  Courts in California, New York, Arizona, Minnesota, Colorado, Hawaii, Iowa, Oregon, Nebraska, Washington and Florida have upheld the admissibility of DRE evidence. As an example of DRE=s acceptance in court, the Los Angeles City Attorneys Office has estimated that 95% of those charged with driving under the influence of drugs are convicted in LA courts.


As of 2006, approximately 6,000 officers nationwide are certified as DREs.  The International Association of Chiefs of Police (IACP) regulates the DRE program. All DREs can trace their expertise back to the 18 Los Angeles DREs that developed the initial formal curriculum in 1986.