Driving under the influence of marijuana (DUIM) is certain to become the new watchword on California highways. Medical marijuana has been a presence in California for many years and the use of recreational marijuana may become legal if California voters approve a proposed November 2016 ballot initiative. But at present, California law has no “per se” law governing the act of driving under the influence of marijuana as it does for driving under the influence of alcohol.
As everyone knows, having a blood alcohol level over .08% while driving in California creates the legal presumption of driving under the influence. Whether you think you are affected by the alcohol in your system or not, if you have a .08% blood alcohol content, you are driving under the influence under the law, no “ifs, ands, or buts.” That is the “per se” law. However, if the cops suspect you are driving under the influence of marijuana, there is no per se law in California. In other words, in order to be convicted of driving under the influence of marijuana, the prosecution must prove you could not safely drive due to marijuana intoxication by the circumstantial evidence. That may soon change.
The move is on to enact a per se law in California that would make any driver who tests positive for a certain amount of THC presumptively driving unlawfully under the influence. Currently only Colorado and Washington State—two states that have legalized the recreational use of marijuana— have per se DUIM laws. In both states, a driver who tests with more than 5 nonograms of THC per millimeter of blood is presumed to be DUIM. As I discussed in a previous post, testing for THC is burdened by a lack of reliable and accurate testing methods. However, scientists are working hard to develop methods to test for THC levels that officers can use in the field.