Reverend Hale and Abigail Williams are the two characters most responsible for the trials in Salem. Reverend Parris also bears some burden of responsibility.
Abigail initiates the action of the play through her lies designed to deflect attention from her transgressions in the woods. Accusing others of witchcraft, she begins a process of hysteria and accusation that results in the trying of many Salem residents.
Reverend Hale lends his authority to Abigail's claims. Flushed with praise and in a resulting state of fervor, Hale applies his authority in support of the trials. Without Hale, the accusations may never have gained enough credence to necessitate the legal action.
For reasons similar to Abigail's, Reverend Parris is also responsible for the trials. He brings in Hale in an effort to remove the stain of blame from his family resulting from the girls' actions in the woods. Parris is worried that he will lose his position in Salem if Betty is seen as having practiced witchcraft. For this reason he puts all of his influence behind the trials.
Hale is undergoing an internal crisis. He clearly enjoyed being called to Salem because it made him feel like an expert. His pleasure in the trials comes from his privileged position of authority with respect to defining the guilty and the innocent. However, his surprise at hearing of Rebecca’s arrest and the warrant for Elizabeth’s arrest reveals that Hale is no longer in control of the situation. Power has passed into the hands of others who start to abuse it, as the craze spreads; Hale begins to doubt its essential justice.
Proctor’s sense of guilt begins to eat away at him. He knows that he can bring down Abigail and end her reign of terror with the information he has on her, but he fears for his good name if his hidden sin of adultery is revealed and doesn’t want people look at him like he looks at them. Proctor’s intense dilemma over whether to expose his own sin to bring down Abigail, thing get for him get worse when Hale’s decision to visit everyone whose name is even remotely associated with the involvement of witchcraft.