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Drug-Impaired Driving: Consultation Document
Theory of Drug Evaluation by Trained Officers
In British Columbia and some other Canadian jurisdictions, officers that do have specific drug assessment training and certification will seek voluntary tests from drug-impaired driving suspects in their investigations. They use a protocol that has been long used by a number of U.S. states, sometimes under highway traffic legislation and sometimes under penal legislation. Legislation in the United States deems the driver to have given his or her consent to chemical testing of his or her blood, breath or urine if that individual is lawfully arrested for driving while impaired by alcohol or drug. This provision known as the "implied consent law" is extremely helpful to law enforcement agencies in the United States. Failure to submit to such chemical tests will result in penal sanctions. Such legislation not only requires the suspect to provide a sample, it also provides the officer with the means to detain and/or arrest the individual in order to secure evidence.
In order to understand the legislative options that follow, it is necessary to be familiar with the nature of the protocol for drug-impaired driving investigations. If conducted properly, the investigation by trained officers will result in an accurate assessment of the suspect's drug impairment, if any, for paragraph 253(a) purposes.
The evaluation of a suspect conducted by a trained peace officer has been developed in California and successfully implemented in many jurisdictions to combat drug impaired driving and is known as the Drug Recognition Expert (DRE) Program. Under this program, officers go through extensive training to enable the officers to conduct various tests and to assess the suspect and determine if there is drug impairment and the nature of the drug causing it. If the officer, after conducting the various tests, concludes that there is drug impairment, she or he then requests a blood or urine sample for analysis. After a blood or urine sample is obtained, it is then analyzed to determine the presence of a drug (not concentration). If the officer has properly conducted the test and accurately assessed the suspect, his or her conclusions on the nature of the drug causing the impairment should match the analysis conducted by the laboratory technician on the blood or urine sample. Where there is such a match, a prosecution will proceed.
Phase I involves the investigating officer's attention being drawn to a pattern of driving which would appear to be erratic or a departure from the norm. At this point, the officer would initiate contact with the suspect driver by pulling the vehicle over and approaching the driver, or the contact could begin upon attending at the scene of an accident. While interacting with the driver, the officer would be able to make physical observations of the driver. These observations may include common indicators of impairment such as slurred speech, blood shot eyes, coordination difficulties while producing a driver's licence, etc. The officer may also ask the driver to perform standardized field sobriety tests (SFST) at the roadside (such as walk-and-turn, one-leg stand, horizontal gaze nystagmus) in order to further establish the officer's grounds for a belief of impairment. If the observations of the officer are consistent with an alcohol-impaired individual, the officer would then make a demand for a breath sample from the suspect. If there is no indication of alcohol, yet the officer suspects drug impairment, the officer could request a saliva sample. The test of the saliva sample takes approximately 5 minutes and can be done at the roadside. However, the saliva "screen" may not have a wide range of drugs that it can identify. Some jurisdictions have used sweat swabs taken across a driver's forehead but like saliva tests, the "screen " may not have a wide range of drugs that it can identify. If based on the general observations or the SFST or saliva/sweat swab test results, the officer reasonably believes the suspect is impaired by a drug; she/he should have grounds to demand the suspect return to the police station for a DRE evaluation.
Phase II of the DRE investigation takes place at the police detachment where a breath sample is obtained to confirm that the cause of the impairment is not alcohol. If in fact the individual's blood alcohol level is consistent with the alcohol impairment indicators, then the officer would not pursue a drug impaired investigation and would simply recommend charges for driving while impaired by alcohol (that is, alcohol would be determined as the cause of the impairment) or driving with a blood alcohol concentration that exceeds the "legal limit".
If the individual has passed the "approved instrument" test, thus eliminating alcohol as the cause of the impairment, the officer would commence performing a series of drug evaluation tests. These tests include:
Eye examination to measure pupil size, vertical and horizontal movement of the eyes, and convergence of the eyes. The pupil size and the ability for movement will fluctuate depending on the degree of impairment and the drug causing it.
A dark room examination is conducted to again measure pupil size and to perform an ingestion examination that allows the officer to determine if there is any drug residue left in either the nasal or throat passage. This examination takes place in a completely dark room where the suspect must remain for approximately 90 seconds prior to an examination with a flashlight. The officer will shine the flashlight from various directions into the suspect's eyes and, with a measuring apparatus, note the various measurements of the pupil and how the eye has reacted to the change in light. The drug ingested will affect how the eye reacts. As well, the officer will then request the suspect to open his or her mouth in order to view the mouth and throat and will further inspect the nasal passage of the suspect.
Sobriety tests requiring divided attention skills are also performed. These tests include balance test, walk and turn, one leg stand, and finger to nose. Each of these tests will not only permit observations of coordination skills, they will further test the ability of the individual to concentrate on numerous tasks simultaneously. Each test will both assist in determining the degree of impairment and provide indicators as to the nature of the drug that has been ingested.
Physical examinations are also performed by the officer, who will check vital signs, including taking the suspect's pulse and blood pressure, checking for muscle tone, and searching for injection sites. The nature of the drug ingested will affect these vital signs and accordingly they are helpful in the drug evaluation.
The officer will then interview the suspect in order to obtain either admissions of drug ingestion or other information that may give assistance in evaluating the suspect.
Performing the drug evaluation tests takes approximately 45 minutes. At the conclusion of this phase, the officer would be in a position to render an opinion with respect to the individual's impairment and its cause.
Phase III of the investigation requires a toxicological examination where the suspect is asked to provide a sample of blood or urine to be analyzed. This phase of the investigation is critical in that the analysis will detect traces of any drug that has been ingested. When the analysis is consistent with the opinion of the evaluator who performed the DRE tests, the forensic evidence then confirms the opinion of the evaluator. It must be underlined that analysis of the blood or urine sample is not for the purpose of indicating when a particular drug was ingested and/or when the individual would have been experiencing impairment caused by the specific drug. It is the officer's evaluation and observations of indicators of impairment that are consistent with the drug found in the blood or urine sample that enables the prosecution to satisfy the court that the individual was impaired by a drug when driving.
In summary, the first phase involves initial contact with the suspect driver at roadside by an officer who, by general observations or "standardized field sobriety tests" administered by a trained officer or by a saliva or sweat swab, may have reasonable grounds to believe that there is drug impairment and proceed with the second phase. The second phase is a more complete series of physical tests at the police station conducted by an officer trained as a "Drug Recognition Expert" who classifies the family of drugs that the suspect is believed to be impaired by. The third phase involves analysis of the sample of blood or urine provided by the driver. There are present concerns with this system (which is currently used in some Canadian jurisdictions, such as British Columbia, but only where the suspect voluntarily participates) in that many drug-impaired drivers will not agree to participate in the testing. Therefore, a legislated system allowing police to make demands is desirable.