A colleague testified that a former cop said ‘I gotta put crazy back in the bag’ after Sandra Birchmore told him she was pregnant

The federal trial of former Stoughton police officer Matthew Farwell recently heard testimony from colleagues who described changes in his behavior in the months before Sandra Birchmore’s death. Prosecutors allege that Farwell strangled the pregnant 23-year-old in her Canton, Massachusetts, apartment on Feb. 1, 2021, to keep her from exposing their long-term sexual relationship.

According to The Boston Globe, Stoughton Police Detective Daniel Barber testified about a car ride in late 2020 when Farwell appeared significantly stressed, around the time Birchmore allegedly told him she was pregnant. Barber testified that Farwell told him, “I gotta put crazy back in the bag,” then tried to reassure him, saying, “It will be all right. Everything will be all right.”

Another colleague, Detective Sandra Barrett, testified that she also noticed a shift in Farwell’s demeanor toward the end of 2020 and into early 2021. She told the court that when she asked whether he was all right while they were at a bar in January 2021, Farwell said he was having problems with a woman in his life. Barrett said he did not identify the woman but told her the problem was “going to take care of itself.”

The defense is arguing that Birchmore’s death was a suicide

PEOPLE reported that Farwell has pleaded not guilty, and his defense team argues that Birchmore died by suicide after Farwell ended their relationship. Prosecutors contend that Farwell, who was 27 when he met 15-year-old Birchmore through a police explorer program, groomed her over many years.

To provide context for the allegations, The Boston Globe noted that prosecutors called forensic psychologist Lisa Rocchio to explain how grooming works. Rocchio testified generally rather than about the specifics of this case, defining grooming as a deceptive and manipulative cycle.

She testified that perpetrators often target vulnerable, isolated individuals to establish control. She also described the stages of grooming as moving from selection and isolation to building trust, desensitization, and eventually sexual abuse.

According to The Boston Globe, the court also heard from Donyea Holloway, Birchmore’s childhood friend. Holloway testified that Birchmore told her she was pregnant in 2020 and identified Farwell as the father.

PEOPLE reported that paternity tests later showed Farwell was not the father of the fetus. However, text messages presented in court suggest Birchmore believed he was, and according to earlier FBI testimony, one message Farwell allegedly sent after she told him about the pregnancy read, “You are truly the worst person on the face of the earth.” Prosecutors also claim that Farwell agreed to get Birchmore pregnant if she agreed to stay silent about their relationship.

Per The Boston Globe, other witnesses, including hairstylist Shauna McGrath, alleged that Farwell and Birchmore were in a long-standing, exploitative relationship. McGrath testified that Birchmore had told her she lost her virginity to the former officer.

Prosecutors are seeking to prove that Farwell’s alleged actions were motivated by a desire to cover up federal crimes, including sexual exploitation and deprivation of rights under color of law. PEOPLE noted that surveillance footage shown to the jury reportedly shows a masked man, whom prosecutors identified as Farwell, entering and leaving Birchmore’s building on the night of her death, just hours before Farwell’s wife gave birth to their third child. The allegations against Farwell have not been proven in court.