The state Office of Traffic Safety states (PDF) that "30 percent of all drivers who were killed in motor vehicle crashes in California in 2010 tested positive for legal and/or illegal drugs, a percentage that has been increasing since 2006."
Not only that, but ...
... the office notes that in fall of 2010 more people were found with marijuana in their systems (8.4 percent of the drivers contacted) than alcohol (7.6 percent) at nighttime roadside surveys conducted in six California cities.
Come to think of it, marijuana is pretty easy to get in contemporary Los Angeles, the nation's pot-shop capital.
The problem for cops is that it's not as easy to trace as alcohol. While you might fail a field sobriety test because you're stoned, no breathalyzer is going to detect marijuana in your system. And even if such detection were possible, there's no standardized schedule of intoxication like like there is with alcohol's blood-alcohol levels.
The office admits as much:
Drug-impaired driving is often under-reported and under-recognized and toxicology testing is expensive. Additionally, because there is no established impairment level for drugs, prosecuting drug impaired driving cases can be difficult.
The bad news for you stoners is that this could change:
OTS announced last month that Sacramento and Orange Counties were awarded federal funding to purchase state-of-the-art drug testing equipment. District Attorney Offices in eight counties are being funded to create special "vertical prosecution" teams that will follow drug-impaired driving cases from arrest through trial.
So remember, friends don't let friends get retarded behind the wheel.