Allover the US where states are developing marijuana programs awaits the discussion of a legal limit to determine if a driver is impaired after using marijuana. States like Colorado and Washington are enforcing a 5 nanogram limit on driver's THC levels to resemble the nations 0.08 blood alcohol level of impairment. The issue with a small limit like 5 nanogram is THC's ability to stay in a user's system long after the effects have worn off. A frequent user of cannabis could test positive after not smoking for 3 weeks, which leaves current testing methods to likely show false positives of impairment. Last week, a bill threatening a 5 nanogram THC limit on Maine drivers was rejected by lawmakers who await more accurate testing for impairment.
The Maine House on Friday voted unanimously to reject the bill, which set a blood level limit that would allow police to charge impaired motorists with operating under the influence.
Supporters say the blood test is needed for public safety, but opponents say there is no scientific consensus on impairment based on blood levels of THC, the psychoactive compound in marijuana.