Except for the execution of Giles Corey, before Act IV the other executions were of less significant citizens of Salem. They did not command the respect and authority that Rebecca Nurse and John Proctor enjoyed. Sarah Good, for example, was mostly treated with disdain, and George Jacobs was not regarded as important. They were, to put it harshly, expendable.
John and Rebecca, however, occupied prominent positions in the village. Both were much admired for their courage and outspokenness. John, especially, had no qualms in criticizing not only Reverend Parris, but also was outspoken about Mr. Putnam and his greed for land. Rebecca was respected for her intelligence and her general good nature. Everyone in the town turned to her for advice, and her reputation spread far and wide; even Reverend Hale commented positively about her when he came to investigate rumors of witchcraft.
Reverend Parris believed that John and Rebecca were part of a faction that was turning the village against him, while Mr. Putnam was constantly in dispute with both about land which he claimed belonged to him. Parris and Putnam's efforts to demonize Rebecca and John are obvious from the start; therefore, if these two were permanently removed, Parris and Putnam's situations would be vastly improved.
Because of the aforementioned factors, the proposed executions of these two characters resulted in greater drama than that of any of the other condemned. It is also important to note that John's execution, in particular, was preceded by an urgent appeal that he sign a confession. He was asked to write and sign his admission of guilt so that it could serve as an open encouragement to others to admit theirs. John tore up his written and signed confession, however, refusing to sacrifice his good name. The fact that he was asked to sign and submit his admission is evidence of the level of influence he had.
In the end, both John and Rebecca were taken to the gallows and lost their lives for standing up for themselves and others. Their deaths indicated a turning point in events in the village, as fewer and fewer people were driven to admit to something they did not do, and the executions soon stopped.
Rebecca Nurse and John Proctor are upstanding citizens of Salem. Prior to their hangings, only the poor and homeless have been hanged. The Nurses own a great deal of land, but they are also greatly respected as a prominent family of Salem. The Proctors are also a respectable family. Though some don't like John, he is respected for his honesty and fairness. To hang these respectable people is a turning point in the trials and is one of the reasons that led to its end.