As the event leader you are responsible for ensuring that the planning process is neither dictated by one person nor hindered by unresolved personality conflicts. Too often infighting happens when work styles differ and clash with others. You have to ensure that everyone has a voice at the table and in the decisions that are made. Avoid being a strong leader. As with any leader you're not always going to be popular with the decisions that are made.
Leadership requires backbone, a sense of fairness and respect from subordinates.