Drugged driving, part 1: Still no standard test available

The .08 percent threshold for blood alcohol content (BAC) for a DUI charge is widely known. It’s been in place for over a decade in every state and is based on a chemical test with a specific number.

Tests for BAC can have serious problems, such as failure to calibrate a breathalyzer properly, contamination of the blood sample, or testing error. However, BAC is based on an objective standard wherein a numerical result is obtained.

This is not the case for intoxicants other than alcohol. Is it true that there is still no standard test for drugged driving?

In Tennessee and most other states, there is no objective chemical test for drugged driving. Some states, however, are experimenting with such tests.

Drug recognition experts

Law enforcement officials generally contend that they can identify drug intoxication, or the combination of drug and alcohol intoxication, by giving additional training to a set of officers called drug recognition experts (DREs). In the early 1990s, the International Association of Chiefs of Police began developing programs to train these officers

In Tennessee, drug recognition officers go through two phases of training. The first is academic, with 72 hours of class work on topics that include field sobriety testing and physiology. There is also a certification phase that requires the completion of at least a dozen evaluations for drug influence as directed by a DRE instructor.

Lack of scientific standards

The problem, however, is that even with additional training, DREs really have no scientifically grounded way to measure intoxication beyond the subjective judgments involved in field sobriety testing.

Moreover, individual variability in reactions to drugs is also generally greater than with alcohol.

This is a problem not only for controlled substances, such as marijuana or methamphetamine, but also for prescription drugs such as Xanax. It is hard to know, for example, whether someone is reacting in a certain way because of a medical condition rather than the drug that was prescribed to treat the condition.

This is a sticky and all-too-common scenario. In a post earlier this year, we discussed the fact that you can be charged with DUI even if the medications were legal.

Are there any objective tests available for drugs?

In part two of this post, we will discuss a California pilot program that is trying to introduce an objective test for drug impairment.

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