The second act takes place in the common room of Proctor's house eight days later. John Proctor returns from a day in the fields and greets his wife, Elizabeth. They make small talk about dinner and the crops, but there is an awkwardness between them. Elizabeth thinks that he went to Salem that afternoon, but Proctor says he thought better of it. Elizabeth tells him that Mary Warren is there today, and although Elizabeth tried to forbid her, Mary frightened her strength away. Mary is now an official in the court, formally accusing people of witchcraft, along with Abigail and the other girls. Elizabeth tells John to go to Ezekiel Cheever and tell him what Abigail said last week - namely that Betty's sickness had nothing to do with witchcraft. Proctor tells her that nobody will believe him, as Proctor was the only one to hear.
Elizabeth is disturbed to realize that Proctor and Abigail were alone together, but Proctor angers at her suspicion. He has tiptoed around the house for the seven months since Abigail left, and has confessed to his sin openly, but Elizabeth remains cold. She claims she does not judge him. Proctor replies that her justice would freeze beer.
Mary Warren enters, and gives Elizabeth a poppet that she made in court that day. Mary reports that thirty-nine people are arrested, and Goody Osburn will hang, but not Sarah Good because she confessed. Mary Warren claims that Goody Osburn sent her spirit out in court to choke them, and often mumbles whenever others turn her away when she begs. Proctor demands proof that Goody Osburn is a witch, and forbids Mary Warren to go to court. Mary says that it is amazing that Proctor does not realize the importance of her work, and insists that she is a court official. Incensed, Proctor threatens her with a whip.
Mary reveals that she saved Elizabeth's life today, for Elizabeth was accused in court. Proctor orders Mary to go to bed. Elizabeth realizes that Abigail wants her dead. Proctor reassures her that he will find Ezekiel Cheever and tell him what Abigail said, but Elizabeth thinks that more than Cheever's help is needed now. She tells him to go to Abigail and firmly renege on whatever promise she may think he made her. Elizabeth believes Abigail must plan to profit from Elizabeth's death, for accusing a respected member of society like her is more dangerous than accusing a drunk or indigent woman like Good or Osburn.
Mr. Hale arrives at the house as Elizabeth and John argue over Abigail. He now has a quality of deference and even guilt. Hale tells them that Elizabeth's name was mentioned in court and Rebecca Nurse was charged. Proctor finds it impossible to believe that so pious a woman could be in the service of the devil after seventy years of prayer, but Hale reminds him that the Devil is wily and strong. Hale questions Proctor on his churchgoing habits, and Proctor claims that he prays at home and criticizes Parris for his wasteful spending habits in church. Hale also notes that only two of Proctor's children are baptized, and asks Proctor to state the Ten Commandments. He names nine of them, but needs Elizabeth to remind him of the tenth – adultery. Proctor says that between the two of them they know all of the Commandments, but Hale says that no crack in the fortress of theology can be considered small.
Proctor says there is no witchcraft happening, and tells Hale how Abigail said Parris discovered the girls sporting in the woods. Hale claims that it is nonsense, as so many have confessed, but Proctor says that anyone would confess if they will be hanged for denying it. Hale asks if Proctor will testify to this in court, and asks if he believes in witches. Proctor answers that he does not believe that there are witches in Salem, but Elizabeth denies any belief in witches at all. When Hale asks Elizabeth if she questions the gospel, she retorts that he should question Abigail Williams about the gospel and not her.
Giles Corey arrives with Francis Nurse, and they tell the Proctors that their wives were taken away. Rebecca has been charged with the supernatural murder of Ann Putnam's babies. Hale, who is deeply troubled, claims that if Rebecca Nurse is tainted, there is nothing to stop the whole world from burning. Walcott charged Martha Corey for the rumor that Giles proposed about his wife reading books.
Cheever arrives to charge Elizabeth. He asks if she keeps any poppets in the house, and she says no. Cheever spies the poppet that Mary Warren made, and finds a needle in it. Abigail had testified that Elizabeth's familiar spirit pushed a needle into her at dinner that night. Mary Warren tells them how the poppet got into the house, and claims that she stuck the needle in it, but Hale questions whether or not her memory is accurate or supernatural. Elizabeth, upon hearing that Abigail has charged her with murder, calls Abigail a murderer who must be ripped out of the world. Proctor rips up the warrant, and asks if the accuser is always holy now. He says that he will not give his wife to vengeance. Hale insists that the court is just, but Proctor calls him a Pontius Pilate. Cheever takes Elizabeth away. Proctor demands that Mary Warren come to court with him and charge murder against Abigail. She warns Proctor that Abigail will charge him with lechery, but Proctor insists that his wife shall not die for him. Mary Warren sobs that she cannot go against Abigail.
While the first act takes place in the "public" setting of Reverend Parris' home, the second act moves into what should be considered the private sphere of the Proctors' home. The conversation between John and Elizabeth Proctor is highly mundane, illustrating the significant tension remaining in the relationship since Proctor's affair with Abigail Williams. Elizabeth Proctor is intensely suspicious of her husband, worrying when he arrives at home late for dinner and adopting a condescending tone when her husband admits that he was momentarily alone with Abigail Williams. Miller establishes Elizabeth Proctor as a morally upright woman, respectable and dignified, yet with an air of superiority that renders her frigid and distant. Proctor feels that Elizabeth has made her home into a repressive atmosphere, continually punishing her husband for his wrongdoing. Still, if Elizabeth adopts a tone of moral superiority it is because she is the superior of her contemporaries, with an unwavering belief in the capability of persons to remain moral.
Miller creates an atmosphere of guilt within the Proctor household that mirrors the similar conditions within larger Puritan society. Proctor has expressed contrition for his infidelity and asked for forgiveness, yet there is no sense of catharsis within his marriage nor ability for full reconciliation. The Proctor marriage is stagnant and stifling, as the fact of John's adultery lingers in every conversation like a giant white elephant. Miller demonstrates this, in particular, when Proctor is unable to recall the commandment against adultery – it is a moment of humor, but it also reflects the crisis of the Proctor marriage. Miller seems to indicate that, like the rest of their Puritan society, the Proctors need an outlet to expiate John's sins and without this means for redemption they are committed to a perpetual obsession with past infidelity.
Two major themes emerge in the second act of The Crucible. The first of these is the line between public and private. The act itself moves from the intimate conversation between husband and wife to more public matters, but the division between these two spheres becomes obscure. Even in this setting, the public discussions of the Proctors' guilt or innocence occurs within the home. More importantly, Reverend Hale and the other court officials use private information for their public matters, such as information about the frequency with which they attend church and their belief in the existence of witches. The court officials investigate all aspects of the suspects' private lives. Under such intense scrutiny, these officials are able to find any information that may be may interpreted as evidence of guilt – not unlike the House Unamerican Activities Commission using everything from religion and sexuality to, in the case of the Rosenbergs, a discarded box of Jell-o as evidence of un-American behavior.
The second major theme of the act is the ambiguity of evidence. This begins even before Hale arrives at the Proctors' home, when Elizabeth, as a betrayed wife, suspects her husband's excuses for coming home late. This continues with Reverend Hale's interpretation of John's forgetfulness of one of the Ten Commandments and the evidence against Martha Corey, which deemed her a witch for reading books. The most significant symbol of this theme in the second act is Mary Warren's poppet. Miller makes it clear to the audience that Elizabeth did not use the poppet as a charm against Abigail Williams, but its presence in her house is quite damning in the view of the court.
The poppet demonstrates that Abigail Williams is more villainous than earlier indicated. In the first act she behaved solely out of self-interest. She was ready to do harm to others, but only to save herself. However, in this instance she purposely frames Elizabeth Proctor out of revenge, planting the poppet as a means to engineer Elizabeth's murder. This event even breaks the icy exterior of Elizabeth Proctor, who deems that Abigail must be "ripped out of the world."
Miller creates a situation of bleak irony in this chapter with the arrest of Rebecca Nurse and Elizabeth Proctor. These characters are the most upright in the play, yet are accused of witchcraft by two of the most ignoble, Thomas Putnam and Abigail Williams. The dynamic of the witchcraft hysteria has created a situation in which the accuser of witchcraft is automatically presumed holy, as Proctor notes, while even the most spiritual character may be suspected of Satanic influence. In this situation the evil of Salem may raise their reputations at the expense of the good.
An additional irony that Miller constructs in the act is in the plot structure. The Proctors and their allies can rely on a single person to save themselves from Abigail Williams' treachery. Yet this person, Mary Warren, is the weakest and most pliable character in The Crucible. She alone has the power to stop the hysteria of the witchcraft trials, but neither the strength nor resolve to do so. Mary requires intense coercion from John Proctor to even consider admitting to the falsehood in court. However, despite her weakness Mary Warren is as dangerous as Abigail, for the guileless girl betrays none of Abigail's malicious bearing and thus appears more overtly innocent. She is a pawn who may be used by the Proctors to prove their innocence, but Miller foreshadows that Mary Warren may be used by Abigail to serve her own purposes as well.
Among the characters in the play, it is Reverend Hale who demonstrates the most prominent character development. While the other characters remain fixed in their particular allegiances and beliefs, Hale demonstrates the debilitating effects of the witchcraft trials by the change in his character. When he reappears in the third act he has none of his old enthusiasm. Although he clings to his belief that proof of witchery can be found in Salem, Hale appears more and more tentative about the results. He demonstrates a strong feeling of guilt for his actions, as shown by his reliance on what he grasps as indisputable evidence. Like Pontius Pilate, to whom Proctor compares Hale, he wants to play only a passive role in the proceedings without any feeling of personal responsibility. Hale's growing disillusionment foreshadows his later repudiation of the court's actions.