BOSTON (AP) — Closing arguments are expected Friday in the trial of a former Massachusetts police officer accused of killing a pregnant woman to keep her from revealing that they had been in a sexual relationship that began when she was 15.

Federal prosecutors say Matthew Farwell killed Sandra Birchmore, 23, and tried to stage her death as a suicide in 2021 after learning she was pregnant with what he thought was his child. At the time, Farwell was a married detective with the Stoughton Police Department, where Birchmore had participated in a youth program as a child.

Lawyers for Farwell, who is now 40, acknowledge he had an extramarital relationship with Birchmore.…