Down here in Australia, the posession of weed is kinda decriminalised. If you are caught with product, weighing in at over 30 grams, you will get done for "intent to distribute". Anything under 30 jingas, and you just get it confiscated and a warning. In the low-level range, like in 2-3 gram weights, they will just pass it off automatically as "personal use", with alot less hassle... and they quite possibly will even turn a blind eye and still let you keep your little stash of greens (I've seen it happen.)...
If you hold a decent attitude towards the officers, in such small "weights", you should be pretty sweet here in Australia. But, the cops down-under are generally pretty cool... and don't thrive for drama.
It's actually also not exactly "illegal" to grow for your own personal usage down here as well.
It's a little bit more complex than that. But, yeah... I can't be bothered going into it now. I'm pretty sure it's one-plant per-head. Per Household, or something... But it's all dependant on the state you're in as well.
Basically, if you were to get caught and a long sentence for posession of Cannibis here in Australia, it would have to be a *REAL* lot of weight... and you more than likely would have other "priors" to your record, to contribute to your current conviction.
I hear in the States, you guys aren't so leniant though... especially in terms of fines/sentences.