TAUNTON - The woman on trial for allegedly driving her boyfriend to suicide via text messages was "involuntarily intoxicated" by her psychiatric medicine, a psychiatrist testified in the Bristol Juvenile Court on Monday (June 12).
Michelle Carter, 20, was in the grips of a "grandiose" delusion that only she could help Conrad Roy find his way to heaven, said Dr Peter Breggin.
"She's not thinking she's doing something criminal. (She's thinking) she's found a way to help her boyfriend," Dr Breggin told Juvenile Court Judge Lawrence Moniz.
Mr Roy, then 18, was found dead on July 13, 2014, from carbon monoxide poisoning in his vehicle, which was parked at a Kmart carpark in Fairhaven, Massachusetts.
Carter is charged with involuntary manslaughter for her role in Mr Roy's suicide.
According to The Boston Globe, Dr Breggin reviewed the texts and Facebook messages between Carter and Mr Roy, describing the former as being overwhelmed by her boyfriend's suicide obsession.
She began taking a new drug, Celexa, in April 2014 for "impulse control issues" and had become "involuntarily intoxicated" by the medication.
This led to a change in the tone of her exchanges with Mr Roy.
Said Dr Breggin: "The text messages show a side of a very troubled youngster. Her parents, teachers and coaches didn't know about this. This was going on largely between her and her peers."
Celexa belongs to a group of anti-depressants known as SSRIs that target the brain's frontal lobe, affecting empathy, decision-making and the ability to feel love.
Dr Breggin said SSRIs disrupt the frontal lobe function more so with adolescents.
He added that Carter organised a fundraiser in memory of Mr Roy after his death, and texted him saying she had raised US$2,500.
But prosecutors have alleged that Carter drove Mr Roy to suicide to attract sympathy.
Texts showed Mr Roy was hesitant to follow through on his suicide plan and had at one point left his pick-up truck.
Carter, however, replied in a text message: "Get the f*** back in the car."
She has chosen to have her case tried by a judge instead of a jury of her peers, an approach sometimes used by defendants in emotionally charged cases who want to bypass a jury in favour of a more dispassionate determination from a judge.