Who confesses to lechery in open court in The Crucible?
Lechery is commonly defined as excessive or offensive sexual desire, and John Proctor admits to being a lecher in response to a question from Judge Danforth in act 3. The judge's question is provoked by John's desperate outburst in court that Abigail Williams, their erstwhile servant, is a whore. John had been involved in an extramarital affair with Abigail while she was in his family's service. When his wife, Elizabeth, suspected the relationship, she dismissed Abigail.
Because of this, Abigail seeks revenge against Elizabeth and has concocted a lie which has led to Elizabeth's arrest on a charge of witchcraft. Abigail also believes that once Elizabeth is out of the way she can resume her relationship with John. John has approached the court to present evidence in the form of a deposition signed by their new maid, Mary Warren, that she, Abigail, and the other girls have been misleading the court all along. More specifically, John wants to prove that Elizabeth is innocent. He has brought Mary to court to testify that the poppet Abigail spoke about was a gift Mary made for Elizabeth, that Abigail saw her make the poppet, and that Abigail saw Mary insert the darning needle into the doll's belly for safe keeping when she was done.
John's shocking accusation that Abigail is a whore, coupled with his damning confession, is a desperate cry to the court to prove that Abigail is a person of ill repute. He has, at this point in the proceedings, heard his character and integrity attacked by various individuals such as Reverend Parris and Mr. Cheever. He has witnessed the court's refusal to accept testimony provided in support of the good character of Rebecca Nurse and has also seen how Giles Corey's accusation regarding Mr. Putnam's greed has been largely ignored. Furthermore, Judge Danforth is of the opinion that the girls are God's instruments used to lay bare the Devil's machinations. In addition, Mary Warren's deposition has been rejected, and the veracity of her testimony has vehemently been attacked by the court's officials.
John feels overwhelmingly dismayed when Abigail denies any wrongdoing and confesses that she has seen Elizabeth keeping poppets in their home. When she starts acting as if she sees spirits, John is driven over the edge and, in a moment of overwhelming passion, confesses to the one thing which he knows will probably doom him. When Francis Nurse tells him that he cannot say what he is saying, John cries out:
No, Francis, it is true, it is true. (Back to Danforth) She will deny it, but you will believe me, sir; a man… a man will not cast away his good name, sir, you surely know that—
John then tells Judge Danforth when and where he conducted sexual relations with Abigail. Abigail refuses to answer the judge when he asks her about John's accusation and threatens to leave rather than answer his question. In an ironically fateful twist, Elizabeth is called in to testify about John's allegations and lies to the court in the false belief that she is protecting her husband. Her action worsens the situation, and Judge Danforth accuses John of lying.
In an effort to show how Abigail is manipulative and a liar, John Proctor finally confesses to having an affair with Abigail in Act 3, Scene 3. When Abby pretends to see spirits and then cries to heaven, Proctor has had enough. He grabs her and calls her a whore. Danforth demands that Proctor prove his accusations, then asks Proctor bluntly, "You--you are a lecher?" Proctor replies, "I have known her" indicating his guilt.
At this point, Proctor chooses to divulge the entire story. John Proctor admits to his affair with Abby which occurred months ago. He also accuses Abby of wishing to be with him after Elizabeth is dead (presumably from being executed as a witch):
She thinks to dance with me on my wife's grave! And well she might for I thought of her softly. God help me, I lusted, and there is a promise in such sweat.
Proctor admits his sin and acknowledges that he understands why Abby might believe that she and Proctor could be together, that Abby might have understood an unsaid "promise" that they would be together after having made love. However, Proctor concludes by shifting the blame from himself to Abby, claiming that, since he rejected Abby, she is exacting her revenge.