Reverend John Hale is the cerebral, yet unproven, witch-hunter whom enters the play in Act I when Reverend Parris summons him to examine his daughter, Betty. She has fallen in a deep trance and, though it pains him to do so, the reverend has no choice but to call for outside help. Hale enters with almost a pompous air to him and immediately asserts himself upon the scene. His arrival also initiates a flurry of activity within the town. Carrying around his large books and projecting an air of great knowledge, the townspeople seem somewhat comforted by his presence and demeanor of self-assured expertise. In Act I Henry Miller describes him with great detail as "a tight-skinned, eager-eyed intellectual. This is a beloved errand for him; on being called here to ascertain witchcraft he has felt the pride of the specialist whose unique knowledge has at last been publicly called for." Indeed, in the early going, he is determined to engage his task head on and with much vigor. He is the initial force behind the organization of the witch trials. He interviews many of the townspeople, all the while probing for confessions and encouraging people to testify. His faith in, not only, the sanctity of his quest, but the divine righteousness of it's conclusions, is unwavering. His initial vindication in drawing out the demons of Betty and Tituba only reinforce his beliefs. As the play progresses, however, his experiences bring forth a change, perhaps more dramatic than that of any other character. .
Through his conversations with John Proctor and Mary Warren, he begins to see a much more intricate explanation for the cries of witchcraft. It is an explanation having much less to do with the occult, and much more to with simple politics and greed. It is not long before he is convinced that Abigail Williams is not telling the truth. During the climactic scene of Act III, he openly opposes the witch trials in court.