What authority argues in their defense and what does this reveal about him the crucible?

The authority that argues in their defense is Reverend Hale, who is the expert on witchcraft. This reveals that he is a man who is more concerned with upholding his own authority and beliefs than with finding the truth. He is willing to overlook evidence that contradicts his preconceptions, and he is quick to condemn those who disagree with him. This makes him a dangerous man, because he is willing to use his power to suppress dissent and persecute innocent people.