The example you saw was from turbo mafia. Its a fast track one . There is hardly time to guess who is who .We need a method because, if people lynch random people, that is suspicious and depressing, and
if people group themselves with a certain faction (ie. townie), it is unreliable because everyone will say they're a townie.
I guess a way to search for suspicious players, is to see if anyone made any awkward, unnatural, seemingly forced posts? In the example game, that is why they were thinking to lynch someone.
Maybe finalbeta will make better game than me he has good experience host. Its good your suggestion will improve my hosting .