Someone, anyone, please tell me anything about this khashoggi, what he was up to. These guys think that becoming a "journalist" is some kind of invincibility cloak. "Can't touch me, I work for wapo yo." A leftie "journalist" gets killed and the rest of the journos chimpout, meanwhile difi's chinese spy gets a bunch of legit US assets killed and it's nothing but crickets. So tired of this shit.
A presumptive test is done for cannabinoids. If positive, a confirmation test is done, in most places only if a plea has not been reached based on the presumptive test. This is to save money. But if a test is done to confirm, they are looking for the active component in your blood, and test to a nanogram threshold. THC breaks down quickly in the system. 20 hours is an arbitrary number and makes your post suspect at best.
I'm not buying what you're selling. No one forced you to drive impaired. I also see a lot of blame shifting. Until you own it, you'll keep getting the same results.