Firstly you vote no lynch for round one you get everyone to investigate the person to their left. You post the infomation you get then you vote no lynch again and investigate the next link in the chain. You are now down to the final three. The chances are that you will now now which kind of cop you are and either the normal or insane cop would have investigated the mole. And now you can lynch said person and win. The only spanner in this work can be if the mafia manage to kill the insane cop and pretend to be that. If you do that you should have a better chance of getting the mole above 50% with only a few different outcomes changing the game. So as I said before it is not a sure win but you can almost make it so.