Roadside Cannabis Tests Are Near, but Skepticism Remains High

More states are legalizing and decriminalizing cannabis or marijuana use. Driving a motor vehicle after ingesting cannabis is as hazardous as alcohol. It slows your reaction time and can limit your peripheral vision and ability to concentrate.

Because DUI is a common and dangerous problem, law enforcement is always on the lookout for more effective ways to enforce their state DUI laws. Screening devices, like a breathalyzer or saliva test that can detect the presence of marijuana or cannabis, are in demand. Soon, officers may have roadside tests to gauge cannabis and other drug intoxication. As more states legalize and decriminalize cannabis use, similar testing devices are in demand.

A DUI conviction is costly. While a first offense is generally a misdemeanor, you face fines, driver's license suspension, and jail time. Extra expenses, such as reinstatement fees and ignition interlock device requirements, can add up. A DUI arrest and conviction will remain on your criminal record for years and, in some states, for your lifetime. It may impact your ability to get a job, get professional licenses, and even find housing.

Overview

State laws around driving under the influence (DUI) are being revised to include intoxicating or controlled substances. Driving under the influence of marijuana or cannabis can lead to a DUI charge in every state. While a few states, like Ohio and Illinois, have established legal limits for cannabis levels in your blood test, many have zero-tolerance policies for any drug intoxication while driving.

Police officers use breathalyzers or breath tests during traffic stops when they suspect you of driving under the influence of alcohol. These handheld devices assess your blood alcohol content (BAC) in a short period of time. Law enforcement relies on chemical tests, such as urine, saliva, and blood sample analysis, to find evidence of impairment by controlled or intoxicating substances.

For years, researchers have been working on a breathalyzer device that tests drivers for cannabis or marijuana impairment. The first cannabis breathalyzers available test for delta 9-tetrahydrocannabinol (THC) levels in breath samples. Oral fluid tests are being experimented with in several states, like Minnesota and Indiana, which test for THC, as well as other controlled substances.

Questions remain on the validity and accuracy of the tests. The need for further research continues.

Drug Impairment Is Difficult To Measure

It took decades of research for alcohol breathalyzers to become accurate and reliable. Breath or oral testing for THC impairment will need its trial period to address a unique set of concerns. For example:

  • THC stays in a person's system longer than alcohol. Measuring the amount of marijuana or its metabolites present isn't as straightforward. THC, the component in the drug that causes impairment, can stay in your body long after the intoxicating effects wear off.
  • It is long established that the amount of alcohol in your blood directly correlates with your level of impairment. The same isn't true with cannabis usage. THC stores in fat cells and releases into your bloodstream for weeks after ingestion. How you take THC can impact your intoxication, as absorption rates vary depending on whether you have smoked cannabis, consumed an edible, or applied it topically.
  • While 0.08% is the legal limit for blood-alcohol concentration (BAC) in most states, it's not as simple to draw a hard-and-fast line with cannabis. A few states have enacted per se laws, setting a legal limit on how much THC is allowable before a DUI charge. Researchers have not reached a consensus on what amount is unsafe for driving.
  • Cannabis intoxication can affect people in different ways. While some may feel a sense of relaxation or euphoria, others may experience anxiety and paranoia.

These issues make it difficult to evaluate when the drug impairs a driver. As more states enact cannabis legalization and decriminalize recreational marijuana use, remember that it is illegal and dangerous to drive while intoxicated by any substance.

Other Methods of Testing Drug Impairment

Without a reliable roadside test available, law enforcement depends on chemical tests to determine drug intoxication. Officers need a reasonable suspicion of intoxication to ask for chemical testing. Methods of testing include:

Field sobriety testing and observation: Also known as roadside sobriety tests, these tests allow the officer to evaluate your balance, attentiveness, response time, and other behaviors. An officer may also look for slurred speech, red eyes, and other signs of drug intoxication. These tests can be subjective and may not provide enough evidence to result in a conviction. However, they can give an officer cause to request chemical tests.

Drug-recognition experts: These specially-trained officers, referred to as DREs, use a 12-step process to determine whether you're intoxicated by a controlled substance. A DRE may take your blood pressure and pulse and perform eye exams and balance tests. Not all courts accept evidence gathered by DREs because they are not medical professionals.

Saliva swab tests: Some police departments, such as in Indiana, have begun trials using mouth swab tests. These tests use a saliva sample to check for the presence of numerous drugs, including THC, methamphetamines, and opioids.  Concerns about false-positive rates exist. Swab testing has yet to catch on in the United States as in other countries, but more police departments are looking into testing them.

Blood, urine, or bodily fluid tests: If a hospital or police station performs chemical tests, the results can take days or weeks. THC also stays in the body for much longer than you feel impaired. Questions remain about the timing of TCH tests and accurate impairment levels.

More reliable and objective standards for drug testing and evaluating THC impairment are needed. This is even more true as medical marijuana and recreational use become legal in a growing number of states.

What Are the Legal Implications of Roadside Cannabis Testing?

Researchers are developing new technology every day. Police departments nationwide are eager for the technology, so more will take part in research to establish reliable roadside drug tests. That means courts, prosecutors, and criminal defense attorneys will play essential roles in evaluating these devices on a case-by-case basis.

If charged with a cannabis or marijuana DUI, it's important to have an experienced cannabis law defense lawyer on your side. A DUI defense lawyer can evaluate your case and provide legal advice.

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