Driving under the influence of marijuana to the extent you are impaired has always been illegal in California, prior to the invention of a new marijuana breathalyzer. California has yet to establish a standard measurable intoxication level for marijuana for law enforcement official use. With a new marijuana breathalyzer, that may be changing.

California police officers have been testing a device by Hound Labs that can detect THC levels in your breath and may be coming to a cop near you. The makers of the device claim that it can detect THC levels in parts per trillion, “a very precise amount of THC in the breath…that measured level will ultimately be correlated to driving impairment at roadside,” Mike Lynn, CEO of Hound Labs said in an interview with The Joint Blog.

No word yet on what level you would need to test at in order to be considered intoxicated. Most likely, a California marijuana breathalyzer would be testing for something in the 10-15 micrograms/liter range, with the ultimate figure to be determined by the legislature.

Of course, a new test for marijuana will face significant legal challenges and public resistance, especially in light of marijuana being legalized via Prop 64, while it remains illegal to drive while impaired.

A marijuana breathalyzer cannot necessarily determine whether a person is impaired or under the influence, according to Paul Armentano, deputy director of the National Organization for the Reform of Marijuana Laws.

“If law enforcement's priority is to better identify drivers who may be under the influence of cannabis, [they should] identify and incorporate specific performance measures that accurately distinguish those cannabis-influenced drivers from those who are not…rather than relying on the detection of compounds that are not consistently associated with behavioral impairment.”

We will be closely monitoring the changes in the law as it continues to evolve. As always, we are here for your questions every step of the way.