If police pull you over under suspicion of impaired driving, they may ask you to take a roadside breath test. While the law does not require you to submit to such a test until after police arrest you, you may agree to take the test and blow into the portable device. If the device shows your blood alcohol concentration to be under the legal limit of .08 percent, you may expect police to send you on your way. Not so fast.

Alcohol is not the only substance that can cause impairment in a driver. In fact, more drivers are behind the wheel after using drugs than ever before, and police are aware that their methods of detecting impairment for alcohol do not work when drugs are the issue. This is why police may turn you over to a drug recognition evaluator if they believe you are impaired but your BAC is below the legal limit.

The standard protocol for drug recognition

A DRE receives special training to determine your possible impairment and to determine which drugs, including valid prescriptions, may be responsible for that impairment. Different drugs may cause different behaviors and reactions in your body. Illinois police use a national standard for narrowing down drugs they suspect you have used, and it includes the following:

  • Consulting with the arresting officer for information about your behavior and other details of the arrest
  • Eliminating any medical conditions that may account for your impairment
  • Taking your pulse and checking your vitals
  • Examining your eyes for pupil reaction and tracking ability
  • Subjecting you to field sobriety tests to measure your coordination and balance
  • Rechecking your pulse and vitals two more times since certain drugs alter these factors over time
  • Examining your muscle tone since certain drugs can cause rigidity or softness
  • Looking for injection sites on your body
  • Interviewing you about your health, habits and drug use
  • Taking blood or urine samples to test for drugs in your system

The process of determining whether you are driving impaired by drugs involves multiple steps, some of which may place your rights in jeopardy. The results of these tests, including anything you say to officers at any time during the process, become evidence against you if the case results in criminal charges. You would be wise to seek legal advice as early as possible if police detain you under suspicion of impairment by drugs.