With the legalization of recreational use of marijuana in California, motorists will have yet another large concern about highway safety when driving on the streets and roads of the state. While the effects of drugged driving can be similar to other impaired driving behavior, such as drunk driving, enforcement will likely be more difficult and complicated by the different manner in which marijuana operates in the body.
Testing for alcohol intoxication is relativity easy. Alcohol is quickly absorbed into the bloodstream, and blood tests can produce a reliable measurement of the amount of alcohol in the blood, which translates to a reasonable approximation of the level of impairment of the driver. But marijuana is different.
Marijuana's active chemical, THC, is not water-soluble, like alcohol, and how it behaves in the body is very different. The THC is absorbed in the fat tissue of the body and then can slowly leach back into the blood. For long-term users, it may create measurable amounts in their blood, even if it has been weeks since they consumed any marijuana.
A California legislator has recently introduced a bill that would allow roadside drug tests of individuals suspected of drugged driving. The problem with this bill is there is no currently available drug test that has anywhere near the reliability of an alcohol test like a portable breath testing device.
This means any test performed by the California Highway Patrol or local law enforcement would be questionable and could be challenged by the allegedly impaired driver. This will make enforcement problematic and likely less successful than efforts to prevent drunk driving.
For anyone involved in a crash with an impaired driver, it will be important to have a very through drug testing performed after the crash, as well as a complete police report indicating the behavior of the driver and any other signs of their impairment from marijuana or other drugs.