RE:Classic Buy on Rumor Dump on NewsThe Regan era produced a lot of negative news on cannabis which, over time, have been proven out to be false. Pretty sure that cigarette comparison to cancer is one of those false stories. People becoming violent on cannabis is another one. I've seen people use it as an excuse for crime but personally I've always seen folks in cannabis as super mellow or happy.
Google "DEA cannabis reschedule letter" it's the letter presented to the DEA to justify rescheduling cannabis and it contains apx 44 reasons behind it.
You should also consider that 44 of the 50 US states voted to legalize already so any concerns appear to have been weighed already by those states