“It’s really difficult to document drugged driving in a relevant way, [because of] the simple fact that THC is fat soluble,” said Margaret Haney, a neurobiologist at Columbia University. “That makes it absorbed in a very different way and much more difficult to relate behavior to, say, [blood] levels of THC or develop a breathalyzer.”
Links
[1] https://ncadd.org/blogs/in-the-news/testing-drivers-for-evidence-of-marijuana-use-is-difficult
[2] http://rethinkpot.org/tags/driving
[3] http://rethinkpot.org/tags/drugged-driving
[4] http://rethinkpot.org/tags/drug-testing