As much Backus research as I have done, this was news to me.
New grounds for divorce in Massachusetts in 1784. The wife of John Backus, a silversmith, received a divorce because he beat her, despite his defense that he knew no other practice because he had seen his father beat his mother. [Source]
The William And Mary Quarterly also weighed in on the Backus divorce, and mentioned the deposition of William Whiting, Jr. [Suffolk, MA, Court Files #129846...].