Marijuana Breathalyzer

November 21, 2019

Several entities, including a technology firm and a team of chemical and engineering academics, have arrived on the scene to promote their version of a breathalyzer device that can detect marijuana use. In recent months, at least two such products have made national news with promises of a product that can give officers a reliable reading.

Delayed Detection

As medical and recreational use, marijuana has become legal in more areas of the country and the potential for impaired driving has increased significantly. In response, law enforcement authorities have sought ways to detect impairment in motorists suspected of driving under the influence of marijuana in the same way that they are able to test in the field for the presence of alcohol on a driver’s breath. Currently, available tests that detect the recent use of pot in blood, urine, saliva, and hair samples take a long time for a lab examination to produce results.

THC-Detection Products

The new breath-testing devices, which resemble alcohol breathalyzers that feature a blow tube and digital display screen, claim to detect particles of tetrahydrocannabinol (THC), which is the high-inducing ingredient in marijuana.

University of Pittsburgh researchers from the Department of Chemistry and the Swanson School of Engineering have been testing a prototype that uses nanotechnology to detect THC molecules by measuring changes in electrical currents that react to residual compounds in the breath that has passed through a carbon tube 100,000 times thinner than a human hair.

California-based Hound Labs has introduced a system that claims to test both the presence of THC and alcohol in the same test. After a test subject blows into a tube for 30 seconds, the cartridge, which is connected to a base station for analysis, produces results in about four minutes.

Problems with THC Tests

THC detection methods have come a long way, but the significance of their feedback is still flawed. Traditional lab tests that find the presence of THC in a driver’s system do not necessarily mean they were driving high at the time the sample was collected, as the detection of THC is possible for up to a month after use. This is because the chemical remains in fat cells long after the high has worn off. Similarly, breathalyzer tests only reveal that the user recently inhaled the drug, not that they are currently under the influence.

West Chester Criminal Defense Lawyers at the Law Offices of Heather J. Mattes Represent Clients Charged with DUI Offenses

If you were charged with driving under the influence of marijuana, contact a West Chester criminal defense lawyer at the Law Offices of Heather J. Mattes. We can help you understand the implications of the charges against you, as well as the limitations of THC-detection techniques used by law enforcement to build a case against you. Contact us online or call us at 610-431-7900 to schedule a free consultation. Located in West Chester, Pennsylvania, we serve clients throughout Chester County, Bucks County, Delaware County, Lehigh County, Montgomery County, and Philadelphia County.

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