Cannabis is still illegal., but the maximum penalty for possession has gone down to two years in jail. If you're over 18 years old, the police will now most likely confiscate the drug and give you a warning rather than dragging you down the Cop Shop.
its very unlikly unless its posession with intent to supply, you can just say its personal smoke, i know someone who had a bar of hash - he was over 18 and they didnt even take it off him because it was personal smoke lol