A voting system under supervision of the leaders and co leaders.

Let us assume that the leader wants to start a war. Or one of the clan member asked the leader to start a war and the leader wants to take the opinion of all the members befor he starts. He can start a voting system inside the clan castle or as a extra tab in the messages or clan mail, with a limited time, like say for 3 hours. And so, when members come online and see it. They can either vote yes or no or not vote. Later when the time is over. The leader or the co, sees the result and takes the decision according to it. Not only that, anything at all can be decided with that. The clan can makes decisions like a team.

Good idea! We too hold elections in our clan, just that we vote through the clan chat.