I think that we talked about this issue from a while in a topic. Imo, I suggest a sort of insurance, every ico/project should pay a fine ~1 BTC in order to post its ANN and bounty topics. This fine should be escrowed by a third trusted person or a staff member and in case of proven scam, the scammed persons could get a part (or all if total amount <1 BTC) of their initial investment.