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There is no ‘dope-alyzer’ for driving while high

Any marijuana in a driver’s blood can trigger DUI charges

Marijuana possession has become legal in nine states and a lower priority for law enforcement elsewhere. But driving under the influence of marijuana or other drugs remains illegal in every state, including South Carolina.

Unlike alcohol, there is no blood or breath test for marijuana intoxication, and no legal threshold that corresponds to the .08 limit for drunk driving. DUI-Drugs (DUID) can be charged for any marijuana in one’s bloodstream, even if the person was totally sober and hadn’t used marijuana that day.

A good DUI defense lawyer will know how to challenge the underlying basis for DUID charges.

Understanding driving under the influence of drugs (DUID)

Technology has not yet caught up with the law. A blood test can detect the presence of THC, the “active ingredient” in marijuana. However, THC stays in the bloodstream long after the person has smoked (or eaten) marijuana. This is especially true for people who use marijuana regularly. The presence of THC in a blood or urine test doesn’t necessarily mean the person was driving while high. It could mean they smoked marijuana a week ago.

The state defines a blood-alcohol level of .08 percent as legally drunk. There is no parallel measure for marijuana — and no “dope-alyzer” device that will indicate whether a driver is under the influence of marijuana. Often unfairly, charges of impaired driving are based on the presence of marijuana, even if just a trace amount. Typically the complaint will include supporting observations such as bloodshot eyes, the distinctive odor of marijuana, or field sobriety tests.

Police must also have a reasonable suspicion to pull a driver over in the first place. A DUID arrest report will usually assert some traffic infraction (illegal turn, broken tail light) or evidence of impairment (weaving, driving below the speed the limit). Does the officer’s dashcam support the report?

Technology – and the law – are evolving

Charges of DUID are commonly paired with charges of drug possession if police find drugs in the car. Challenging the legality of the initial traffic stop also calls into question any subsequent searches of your person or vehicle – and any resulting drug charges.

Marijuana does not affect drivers the same way as alcohol, so traditional field sobriety tests are not always an effective (or fair) gauge. Law enforcement experts are developing new field sobriety tests specifically geared toward suspected marijuana use. Industry experts are also working on breath and blood testing devices that are more reliable indicators of how recently a person smoked and whether they are impaired.

Hopefully technology catches up with the law, especially if marijuana is one day legalized in South Carolina and more citizens partake. In the meantime, make sure you get experienced legal counsel if you are accused of driving under the influence of drugs.

Source: Can sobriety tests weed out drivers who’ve smoked to much weed? (NPR)