At the time of the first allegations of witchcraft Willard was serving as a constable in the village of Salem and his duties included bringing the accused before the court. Soon, however, he began to doubt the truth of the accusations and in May 1692 he refused to make any more arrests. In retaliation Ann Putnam, Jr. and others accused him of witchcraft, and of murdering thirteen citizens.
Some of his in-laws made accusations. Margaret Wilkins Knight would tell the court that Willard had previously beat his wife. Samuel Wilkins testified that he had repeatedly been irritated and afflicted by something in a dark colored coat -- and that it was John Willard. John Wilkins would blame the death of his wife, after having delivered a baby, on John Willard... [p]atriarch, Bray Wilkins, would say that he came down with his illness after John Willard had looked at him with an evil eye. Willard was found guilty of witchcraft on August 5, 1692. On August 19, 1692, he was hanged, along with John Proctor, George Burroughs, George Jacobs, Sr., and Martha Carrier. Willard maintained his innocence until the very end.