The Massachusetts woman who encouraged her boyfriend's suicide through text messages was taken into custody on Monday after the state's high upheld her involuntary manslaughter conviction.
Michelle Carter, 22, must begin serving her 15-month stay behind bars immediately, Bristol County Juvenile Court Judge Lawrence Moniz ruled from the bench in Taunton, Mass.
Carter's defense lawyers had asked Moniz to keep their client free during their attempts to have the case heard by the U.S. Supreme Court. And earlier on Monday, the Massachusetts Supreme Court rejected Carter's emergency motion seeking to delay the sentence from being imposed.
That same state high court on Wednesday upheld Carter's 2017 conviction for involuntary manslaughter for her role in the July 2014 suicide of Conrad Roy III, 18.
Carter was on the phone with Roy as he inhaled carbon monoxide inside his pickup truck in Fairhaven, Massachusetts. Carter was 17 at the time and only about a month out of a psychiatric hospital when Roy took his own life.
Carter opted against a jury and Judge Moniz found that she contributed to Roy's death by telling him to "get back in" his truck as it was filling with poisonous fumes.
"The evidence against the defendant proved that, by her wanton or reckless conduct, she caused the victim's death by suicide," according to last week's high court opinion. "Her conviction of involuntary manslaughter as a youthful offender is not legally or constitutionally infirm. The judgment is therefore affirmed."
The high court cited Carter's own words, in text messages to friends after Roy's death, as supporting her conviction.
"As the defendant herself explained, and we repeat due to its importance, `[The victim's] death is my fault like honestly I could have stopped him I was on the phone with him and he got out of the [truck] because it was working and he got scared and I f--king told him to get back in,'" the court wrote in its decision.
Editor's note: If you are looking for help, please call the National Suicide Prevention hotline at 1-800-273-8255.
David K. Li is a breaking news reporter for NBC News.