Did you get through 2nd grade? Smoking is the verb. Pot is the noun. A noun is a person, place or thing. In this case, a "thing". The charge is "Possession of a controlled substance". This "thing" (pot) is a controlled substance. When you go to court, the cop must have physical evidence, the "thing". Without it he has no case. duh?
Let me explain it to you like you were (are?) a 5 year old. In order to throw(verb) a ball(noun), you must have a ball. In order to ride(verb) a bike(noun), you must have a bike. The verb is the operator, the noun is the operand.
This is the syntax of a logical operation. Debating it is just childish to anybody who speaks the english language.
To reiterate, people are inprisioned for "possession" of pot. They are inprisoned for the noun, not the verb. Indeed thay can also inprisioned for culitvation (a verb) and for distrubution (a verb).
What really is you point? Your argument might just as well be "has anyone been imprisioned for killing(verb) a man(noun)". Killing is not illegal (like squashing a bug), but killing a man could be. I don't have a dog in this pot/liberteen fight.
Please name ONE person sentenced for smoking pot.
Just one.
Please?