The Drug Recognition Expert (DRE) evaluation is a standardized procedure for determining impairment by drugs or a drug and alcohol combination. The evaluation involves the observation of visual clues and vital signs, questioning and the provision of a bodily fluid sample for analysis.
It consists of 12 steps:
- A breath test to rule out alcohol as the major cause of impairment;
- An interview of the arresting officer by the drug recognition expert (The effects of some drugs are short-lived. An interview with the arresting officer is essential in order to give the drug recognition expert a clear idea of what symptoms were observed at the roadside, or place of first contact with the subject.);
- A preliminary examination of the subject;
- An eye examination (The subject’s eyes are examined for involuntary jerking when looking to the side or looking up following a stimulus from side to side or up and down. The ability of the subject’s eyes to converge is also tested.);
- A series of divided-attention tests (These standardized tests check the subject’s ability to multitask. Subjects are asked to: listen to instructions while maintaining a stance, maintain a stance with eyes closed, walk a straight line, turn in a prescribed way and walk back, stand on one foot in a prescribed way for a certain amount of time, and touch the tip of their nose with the tip of their finger as instructed. These tests are usually easy to complete when sober, but difficult or impossible when impaired by a drug or alcohol.);
- The examination of vital signs (Blood pressure, temperature and pulse are taken.
- A darkroom examination of pupil sizes (This includes an examination of the subject’s nasal and oral cavities.);
- A check of muscle tone;
- An examination of typical injection sites on the person’s body;
- The rendering of an opinion by the drug recognition expert;
- An interview with the subject;
- And the provision of a bodily fluid sample.
The DRE evaluation has been designed to check for the presence of seven classes of drugs. These are depressants (including alcohol), inhalants, PCP (phencyclidine), cannabis, stimulants, hallucinogens and narcotics (opiates like heroin and morphine). Research has shown preliminary DRE evaluations (i.e. without the toxicology results from bodily fluid samples) to be more than 80% effective. Charges are not laid without confirmation of preliminary evaluations through toxicology.
The DRE program was developed by the Los Angeles Police Department and standardized by the National Highway Traffic Safety Administration in the U.S. in the early 1980s. DRE training is a crucial tool for police as they encounter drivers impaired by drugs other than alcohol, such as marijuana, on the highways. By helping determine impairment by non-alcohol drugs or combinations of drugs and alcohol, drug recognition experts can save lives.
Besides helping to keep drug-impaired drivers off the nation’s roadways, DRE testing can also rule out drug impairment in drivers who have a medical condition, such as a neurological injury, and steer these people towards appropriate medical attention. Drug recognition experts can assist in other situations too, such as when dealing with intoxicated prisoners and assessing whether they require emergency medical services.