In England the cops dont care really my mates have got done for it. If you admit to having it then they just put it down the drain and give you a caution. My mates sparked up in a club at the bar and he got hauled out of there but nothing came from it. They let dealers off aswell there was a cannabis factory near where I live it was a big haul about 500 plants but coz it was shit weed they just gave him community service. Most cops want it legal because it is just paper work without a reward.
Think about it cop stops a teenager with a half arrest him takes him in about 2 hours till there back on the streets. They could have spent that time catching someone that they could get some brownie points for.