How police evaluate drivers for drug impairment

Police pulled you over under suspicion that you were driving while impaired. You consented to a roadside breath test, and police were surprised to see no alcohol registered in your blood. You may think the next step is for officers to hand you your license and registration and wish you a pleasant evening. However, you may have much more ahead of you.

More police agencies in California and across the country have trained drug recognition evaluators (DREs) on their teams. In fact, the development of the DRE program occurred in this state with the collaboration of the National Highway Traffic Safety Administration. If police determine you may be impaired but not by alcohol, you may face the lengthy evaluation of a DRE at the police station.

The DRE process

Unlike alcohol impairment, drug impairment may come from numerous sources, from newly legalized marijuana to powerful prescription opioids or illegal substances such as heroin. One test does not exist to determine whether you or any driver is under the influence of drugs, which drugs and how much of the substance you may have consumed. However, after ruling out alcohol, a DRE uses a 12-step examination to try to determine whether you are under the influence of drugs, and the evaluation process may include these tests and others:

  • Questioning you and taking your pulse to rule out any injuries or health conditions that may mimic impairment
  • Studying your eye movements and reactions to light, which certain drugs may alter
  • Putting you through a series of field sobriety tests, which are the same as those used to determine alcohol impairment
  • Rechecking your vitals, which happens numerous times throughout the evaluation process
  • Checking your body for injection sites
  • Interviewing you about your drug use
  • Performing toxicology tests on your blood or urine to confirm the DRE’s opinion

The DRE also meets with the arresting officer to learn what the officer observed in your appearance and behavior that aroused the suspicion that you may be impaired. As you can see, many of these steps may be subjective in nature.

Protecting your rights

Before police conduct these tests or interviews, they must inform you of your right to remain silent and seek legal counsel. While you may hear these words, you should also be prepared for police to encourage you to go forward with the tests for your own good. However, it is always wise to refuse to answer questions or participate in any potentially incriminating activities until you obtain the advice of an attorney.