Marijuana and DUI - Are Sober Drivers Being Arrested?
Posted on Sep 29, 2011
Drivers under the influence of marijuana or other drugs are often charged with DUI. However, blood testing seems to be the only accurate measure of determining how much THC is in the body (THC can show up in urine nearly 2 weeks later), and blood testing is not done roadside after a traffic stop.
It is more important to determine driver impairment than THC blood levels, since those levels vary depending on many factors, including frequency of marijuana use. This article contains great information on some of the science of THC levels.
It also explains that field sobriety tests are being developed in an effort to more accurately determine which drivers are actually impaired, and which ones are perfectly sober even if trace amounts of THC are detected.