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Nicholas W.

William R.

Criminal Defense Experience - 40+ Years

How Can a Drug Recognition Expert (DRE) Tell That You’re Driving Under the Influence of Marijuana?

Drug recognition experts, or DREs, are police officers with training on recognizing the signs of a driver under the influence of a substance, be it marijuana, cocaine, methamphetamine, or prescription painkillers, among other substances.

Also known as drug recognition evaluators or technicians (depending on jurisdiction), DREs administer a test on drivers suspected of driving while high or impaired. It’s similar in scope to traditional roadside testing for driving under the influence of alcohol, with a few differences.

A “drug influence evaluation” generally begins with the officer’s preliminary investigation following a traffic stop, e.g. looking for bloodshot eyes, slurred speech, an odor of alcohol or marijuana, etc. In this aspect, it’s much the same as a typical DWI case, where the officer checks for signs of intoxication. An officer will typically rule out alcohol first (though not always), then move on to ascertain whether there’s the presence of other drugs in the driver’s system.

The Marijuana Mouth Swab Test

The science and methods of testing for marijuana continue to evolve, but the primary test is the mouth swab. As the Los Angeles Times and many other media outlets reported in 2017 (in the lead-up to legal recreational marijuana use in California in 2018), the Dräger DrugTest 5000 gives officers the ability to administer a preliminary test for the presence of active THC compounds in a driver’s system.

Why Officers Take DUI Marijuana Seriously

The easy answer is that it’s against the law – but more importantly, no matter how you slice it, marijuana does change one’s perceptions and motor functions, and this may have a negative impact on some people’s ability to drive. Because of this, the government treats DUI marijuana much the same (in terms of criminal punishment) as DUI alcohol.

Any form of impaired driving could potentially cause a car wreck, which in turn risks the lives of drivers, passengers, pedestrians, bicyclists, etc.

The wide disparity in terms of marijuana’s effect on one driver to another – a regular user of marijuana vs. an occasional user, for example – won’t matter much if you’ve been pulled over and arrested for DUI.

Both drivers would face charges.

Call Christoph Law Offices

If you’ve been arrested for DUI, call attorneys Nicholas and William Christoph at 760-487-6830. We’re located in Vista, Calif., across from the courthouse, where we’ve been for more than 35 years.

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