Martha Corey stands before Judge Hathorne in the beginning of Act III. She is accused of reading fortunes, technically she is accused of witchcraft.
"Hathorne: Now, Martha Corey, there is abundant evidence in our hands to show that you have given yourself to the reading of fortunes. Do you deny it."
"Martha: I am innocent to a witch. I know not what a witch is."
"Act Three is set in the side room of the Salem meeting house, which has now become the General Court. The proceedings of the court, taking place in the next room, are audible. Judge Hathorne questions Martha Corey, who has been accused of reading fortunes and harming the accusing children."
Martha is also accused later on of bewitching Mr. Walcott's pigs. Martha Corey raises pigs and sold pigs to Mr. Walcott, unfortunately for Walcott, the pigs he bought from Mrs. Corey died. His subsequent pigs died, and he has accused Martha Corey of putting a spell on them.
Martha's response is that Walcott does not take proper care of his pigs, and if you don't feed a pig properly it will die.
Judge Hathorne does not make any accusations of Martha Corey although she is accused of being a witch by a member of Salem village. In Act 1, Giles Corey tells Hale that his wife reads strange books that prohibit him from being able to pray in their home. Sometime during the events of Act 2, Martha Corey is accused of witchcraft. It is in Act 3 that Hathorne reveals why she has been accused. Years ago she sold some cows and since those cows have now died, the man who bought them accused her of witchcraft and those strange books that Giles mentioned in Act 1 were used as evidence.