When someone propses somthing, I respond to the post and ask what the rest of the list wants. More often than not, I'm told that I am being extremely fair. I have told them several times that I want them to be completely honest with me as to what they think. You make decisions based on your objectives. That's part of ownership.
Ownership depends on the list.
Many discussion mailing lists are community efforts. On most lists, the subscribers make or break the forum. Typically, the admin provides guidance but doesn't provide most of the energy in the discussions. With most mailing lists, I have no quarrel with the admin both establishing and enforcing the rules. Typical mailing lists are NOT democracies.