Warning: This story contains content that may disturb some readers.
A woman who convinced her suicidal boyfriend to kill himself in streams of text messages and told him to "get back in" a truck filled with toxic gas will be imprisoned.
Michelle Carter, 20, was on Friday (NZT) sentenced to 15 months in jail for involuntary manslaughter of her then-boyfriend Conrad Roy III.
The judge said her final note to the 18-year-old caused his death, by carbon monoxide poisoning.
He was found dead in his pickup truck in the parking lot of a Kmart on July 13, 2014. At the time, Ms Carter was 17.
The court heard how up until he passed out Ms Carter was on the phone with him, and when he had doubts and exited the truck, she ordered him back in.
In dozens of text messages, she urged the depressed teen to follow through on his talk of taking his own life.
"You can't think about it. You just have to do it. You said you were gonna do it. Like I don't get why you aren't," Ms Carter wrote.
"The time is right and you are ready ... just do it babe," Ms Carter wrote on the day he killed himself.
The trial was closely watched around the world, in part due to the coercive tone of the text messages, the precedent it now sets for whether text messages are protected speech, and determining what it means to be present at the scene of a crime.
The notoriety of the case turned Ms Carter into a hated figure in social media, where people tweeted threats such as "I hope you rot in jail forever", and, "Michelle Carter is a witch".
The case weighed on more than 1000 Facebook and text messages exchanged between pair over two years.
Juvenile Court Judge Lawrence Moniz gave Carter a 2½-year jail sentence, but said she had to serve only 15 months of that. He also sentenced her to five years of probation.
Mr Roys' father told the court he was heartbroken.
His 13-year-old sister, Camden Roy, said she was "haunted" by the realisation that she'll never see her brother wed or be an aunt to his children.
Ms Carter's lawyer, Joseph Cataldo, asked the judge to spare his client jail time and instead give her five years of probation and mental health counselling.
He said throughout their relationship and the event she was struggling with mental health issues of her own; eating disorders and depression.
Prosecutor Maryclare Flynn called probation "just not reasonable punishment" for her role in his death, and sought the maximum sentence of 20 years incarcerated.
If you wish to talk to someone about mental illness or suicide you can call Lifeline on 0800 543 354, or the Depression Helpline on 0800 111 757.