It’s impossible to accurately test scientifically whether someone has just smoked a joint. They can only estimate to a certain probability but how can you be convicted on probability?

Research closing in on a breathalyzer for marijuana — but there’s a problem
blog.seattlepi.com
If an officer of the law pulls you over and suspects you’ve been using marijuana and might be impaired, the officer performs a field test. And if that leads to greater suspicion, well, things can e… …read more