The legalization of marijuana has been in place in Colorado for several years now and may seem to some as simply being a normal part of living in Colorado these days. Like alcohol, marijuana has an impairing effect. That means that Coloradans who get high and get behind the wheel of a car can be charged with driving under the influence. However, determining when a person is too high to drive is proving to be complicated for police officers and courts.

Under current law, a motorist can be charged with DUI if his or her blood has more than five nanograms of active tetrahydrocannabinol (THC). THC is what gives a person a “high” when they smoke or otherwise ingest marijuana. However, THC can stay in a person’s system, particularly their fat cells, long after the “high” has worn off. Simply put, the presence of THC does not necessarily mean a person is impaired.

Moreover, reliable roadside tests for detecting drugged driving are still being developed. Police still rely on field sobriety tests, including blood tests, the one-leg stand test and other roadside sobriety tests. However, there is no gold standard test that is reliable enough to determine if a person is too high to drive.

As it stands, some officers in the state have determined that if a motorist doesn’t show any sign that they are impaired by marijuana, they will not act to arrest the motorist for DUI. Some prosecutors likewise have stated that they are not comfortable criminally prosecuting a motorist for DUI if the only basis for the charge is the five-nanogram limit.

Still, this opinion isn’t shared by all officers and prosecutors and there are too many instances of people being charged with DUI on suspicion of marijuana use when in fact they are sober. Thus, it is still worthwhile to fight such charges in order to avoid the harsh consequences that come with a DUI conviction.