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The Law Blogger is a law-related blog that informs and discusses current matters of legal interest to readers of The Oakland Press and to consumers of legal services in the community. We hope readers will  find it entertaining but also informative. The Law Blogger does not, however, impart legal advice, as only attorneys are licensed to provide legal counsel.
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Tuesday, November 7, 2017

Roadside Saliva Testing for Marijuana is Here

People are going to abuse marijuana just as they do alcohol. Keeping drivers that are too stoned off the road, just like with drunk drivers, is the task at hand for law enforcement.

The Michigan State Police will soon begin administering roadside saliva tests for THC; the one-year pilot program rolls-out this month in 5 counties, unnamed in last year's enabling legislation. The five counties finally were revealed this week: Berrien, Delta, Kent, Washtenaw, and St. Clair.

This new law enforcement tool comes in an era of decriminalization and at the end of the prohibition of marijuana. For example, Canada will legalize marijuana for recreational use this summer for all 9 provinces. In the process, they too are rolling-out a roadside saliva test designed to catch stoned drivers.

Despite ever more progressive marijuana policies among the states, the drug nevertheless affects driving. Consequently, its use is addressed in the Motor Vehicle Code here in Michigan; criminal sanctions can result from stoned driving.

A challenge for legislators, prosecutors, judges and law enforcement is measuring the quantity of the drug in the driver's body. There is no consensus among experts regarding how much marijuana impairs driving skills.

Unlike alcohol, THC and other controlled substances are difficult to measure with the accuracy required to support a conviction. Today, officers are trained to watch for and observe signs of impaired driving.

A .08 blood alcohol level -which can be easily and reliably determined- is universally accepted as a threshold for the legal operation of a motor vehicle. There is no comparable standard when it comes to marijuana.

Because driving under the influence of marijuana is difficult to detect, Michigan is utilizing specially trained state troopers known as Drug Recognition Experts. These DREs use a 12-point evaluation in making the determination of a driver's impairment by drugs.

Part of the DRE training involves administration of the saliva test. The test is designed to detect marijuana, amphetamines, methamphetamines, benzodiazepines, cocaine and opiates.

Defense lawyers are calling foul, characterizing the saliva tests as "junk science". Not even preliminary breath tests for alcohol -also administered at the roadside- are admissible in court. Rather, the preliminary test results may establish probable cause to conduct a more accurate but more intrusive search: a blood test.

Refusing the saliva test is treated in the same manner as refusing a preliminary breath test when suspected of drunk driving: liability of a civil infraction and exposure to law enforcement being able to use the refusal as a component of the probable cause to arrest calculation.

Obviously, officers making routine traffic stops cannot haul everyone they suspect of driving under the influence of drugs into a nearby hospital for a blood draw. If the saliva test is positive for any of the above-referenced substances, then probable cause is established to conduct a blood screen; a seizure under the 4th Amendment.

Last July, the National Highway Traffic Safety Administration sent a detailed report to Congress calling into question whether the roadside saliva tests could even properly detect THC, let alone verify an amount per milliliter of blood deemed to be officially "stoned". The report concluded:
Many studies, using a variety of methods, have attempted to estimate the risk of driving after use of marijuana. While useful in identifying how marijuana affects the performance of driving tasks, experimental and observational studies do not lend themselves to predicting real-world crash risk.
Some studies suggest that a person's tolerance of marijuana has a significant impact on whether they can drive while stoned -i.e. the more you smoke, the better driver you become while high- while other studies point to the increased number of crashes where the driver had some level of THC in their bloodstream.

The current state of the law is that any amount of active THC in a driver's bloodstream is illegal. As we know, however, the Devil is in the details. False positives, based on residual amounts of THC in the bloodstream, are far too common with saliva swabs.

With the science of the available testing devices lagging behind, we will monitor this pilot program and report on its progress and relevant developments. A scientific breakthrough relative to the collection and processing of forensic data could come at any time.

Meanwhile, if you use marijuana, do us all a favor and don't drive stoned.

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