By ALANNA DURKIN RICHER
Associated Press

TAUNTON, Mass. (AP) - A Massachusetts woman who sent her suicidal boyfriend a barrage of text messages urging him to kill himself was jailed Monday on an involuntary manslaughter conviction nearly five years after he died in a truck filled with toxic gas.

Michelle Carter was sentenced to 15 months in jail in 2017 for her role in the death of Conrad Roy III, but the judge allowed her to remain free while she appealed in state court. Massachusetts' highest court upheld her conviction last week, saying her actions caused Roy's death.

A lawyer for Carter had argued the 22-year-old should stay out of jail while her defense team takes her case to the U.S. Supreme Court. Her attorneys said in court documents that she has no prior criminal record, hasn't tried to flee, and has been receiving mental health treatment.

But a judge ruled Monday that she should start her sentence. Earlier in the day, Massachusetts' highest court denied an emergency motion filed by her lawyers to keep her out of jail.

Carter showed no discernible emotion as she was taken into custody, though her shoulders sagged as she stood and prepared to be led away.

Roy's aunt expressed relief Monday, saying his family believes justice had been served even though the case had been a long and difficult ordeal for them.

"We hope that no one else ever has to feel this pain," Becky Maki said. "His life mattered."

An attorney for Carter vowed to continue to appeal.

"Make no mistake, this legal fight is not over," Joe Cataldo said.

Carter was 17 when Roy, 18, took his own life in Fairhaven, a town on Massachusetts' south coast in July 2014. Her case garnered international attention and provided a disturbing look at teenage depression and suicide.

Carter and Roy both struggled with depression, and Roy had previously tried to kill himself. Their relationship consisted mostly of texting and other electronic communications.

In dozens of text messages revealed during her sensational trial, Carter pushed Roy to end his life and chastised him when he hesitated. As Roy made excuses to put off his plans, her texts became more insistent.

"You keep pushing it off and say you'll do it but u never do. It's always gonna be that way if u don't take action," Carter texted him he on the day he died.

But the juvenile court judge focused his guilty verdict on the fact that Carter told Roy over the phone to get back in his truck when it was filling with carbon monoxide. The judge said Carter had a duty to call the police or Roy's family, but instead listened on the phone as he died.

"After she convinced him to get back into the carbon monoxide filled truck, she did absolutely nothing to help him: she did not call for help or tell him to get out of the truck as she listened to him choke and die," Supreme Judicial Court Justice Scott Kafker wrote in the court's opinion affirming her conviction.

At trial, Carter's lawyer argued Carter had initially tried to talk Roy out of suicide and encouraged him to get help. Her attorney said Roy was determined to kill himself and nothing Carter did could change that.

Her appellate attorneys said there was no evidence that Roy would have lived if Carter had called for help. They also argued there wasn't enough evidence to prove that Carter told Roy to get back in his truck.

Her phone call with Roy wasn't recorded, but prosecutors pointed to a rambling text that Carter sent to a friend two months later in which she said called Roy's death her fault and said she told Roy to "get back in" the truck.

Daniel Marx, who argued the case before the Supreme Judicial Court, said last week that the court's ruling "stretches the law to assign blame for a tragedy that was not a crime."

"It has very troubling implications, for free speech, due process, and the exercise of prosecutorial discretion, that should concern us all," he said.

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