Here's a historical detail that Barry drops that ties the past with a current suspect, Rose:
"With the exception of Sarah Good, who was thirty-nine, the women executed on July 19, 1692, were much older, ranging in age from fifty-seven to seventy-one. Some were homeless or nuisances to the community: indebt, outspoken, or otherwise troublesome. It made him think of Rose."
Rose is homeless, deranged, and is now accused of a crime that he does not think she committed. No wonder Rafferty draws the parallel.