The LD50 is pretty important if we're evaluating the safety of the drug, especially if it's easy to ingest that amount.

> cannabis half life is anywhere from 1 to 10 days. Considering caffeine's 5-6 hours and fact people usually stay away from coffee after 3PM - it's very realistic to feel cannabis for days after use.

The duration of psycho-effects is not the same thing as the half-life. The half-life of cannabinoids is not too important, as the compounds are absorbed by fatty acids and released slowly over time into the body. The actual high for a typical dose lasts a few hours; you might feel groggy for about a day, maybe two if you're an infrequent user. As for your personal experience, I know people who can function normally in conversation on weed. Personally, I can't, but other things like driving and coordination tasks are no problem for me.

Downvote me to oblivion on this - I don't care. If you drive while high you are threatening the lives of others just for kicks. You don't want that blood on your conscience if something goes wrong. No your reaction times, focus, and judgement are not the same. They just aren't. I am not anti-marijuana by any stretch but there is a time and a place for it. Driving is not that time.

Have you ever driven without getting a full night's sleep? Wouldn't you consider that the same kind of offense since it reduces your reaction time and focus?

I'd like to see some data on the increased risks of driving while under the influence of marijuana before I lump it in with alcohol but saying that ANY reduction in focus or coordination means you are a threat to other drivers doesn't seem rational as long as you are still above a minimum threshold.

"Acute cannabis consumption nearly doubles the risk of a collision resulting in serious injury or death; this increase was most evident for studies of high quality, case-control studies, and studies of fatal collisions" - https://www.bmj.com/content/344/bmj.e536

I don't hate weed. Quite the contrary! But the whole point of a smoke is to put you in a different place and that place is not conducive to the safety of those around you while steering two tons of metal at 70MPH. I'll take us off on a different and probably unpopular tangent - if you say that marijuana makes absolutely no difference to your baseline judgement, reflexes, focus, etc... then you might be hitting the pipe a bit too often (i.e., massive tolerance and habituation) and it's maybe time to consider scaling back.

This is your problem when you cannot use it responsibly. (E.g. dosage, some people are sensitive.)

The employer can always just fire you for being unable to perform job duties regardless of cannabis laws, if it is a repeat incident. They cannot just use cannabis use alone or drug test results to make an argument.

Interestingly enough, mildly drunk or hangover professional drivers routinely cause accidents which even sometimes kill people.