From Dragon Eye Atlas
The arbiter is a trusted person, not involved in any way in the dispute, that both parties accept as impartial. Very often, though not always, this is a local priest.
The arbitration process is simple. First, both parties get to tell their side of the story, while both the arbiter and the other party listen. Then, the arbiter will attempt to arrange an agreement that both parties are happy with. This might take some time and negotiation, but most arbitration cases are actually resolved this way, with an agreement all sides support.
Formally, the question is resolved in a vote, with each party and the arbiter having one vote. This way, if no agreement can be reached, the arbiter will offer up a solution and as long as he can convince at least one of the parties to accept it, the matter can be decided this way. Rarely, the arbiter's fair solution is refused by both parties, in which case the final step of the process involves bringing in a second arbiter. Now, the two arbiters can, if they agree on a solution, make a ruling against both parties' wishes. This very rarely happens.
There is no appeals process or overturning of an arbitration decision, and all decisions are final.