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TAUNTON (CBS/AP) – A juvenile court judge has found a Plainville teenager guilty of involuntary manslaughter after she was charged with sending her boyfriend a barrage of text messages encouraging him to kill himself.

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Michelle Carter was in tears as Judge Lawrence Moniz began to read his decision in the death of Conrad Roy, who was found dead in his truck of carbon monoxide poisoning in 2014.

Moniz announced his decision on Friday in Bristol Juvenile Court.

Carter, now 20 but 17 years old at the time of Roy’s death, waived her right to a jury trial, meaning that members of the community did not render the decision; Moniz acted solely as jury.

The judge focused his ruling on three words Carter said to the 18-year-old Roy after he climbed out of his truck as it was filling with toxic gas and told her he was scared.

“Get back in,” Carter told Roy, according to a friend who testified that Carter described the conversation in a text message to her about a month after Roy died.

“This court finds that instructing Mr. Roy to get back in the truck constituted wanton and reckless conduct by Ms. Carter, creating a situation where there is a high degree of likelihood a high degree of harm would result to Mr. Roy,” Moniz said.

He said Carter, then 17, had a duty to call someone for help when she knew Roy was attempting suicide. Yet she did not call the police or Roy’s family, he noted.

“She did not issue a simple additional instruction: Get out of the truck,” the judge said.

Carter faces up to 20 years in prison after being convicted.

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The prosecution asked for Carter’s bail to be revoked, but Moniz allowed her to remain out on bail until her sentencing on August 3.

“This has been a very tough time for our family. We’d like to just process this verdict,” Roy’s father, Conrad Roy Jr., told reporters after the decision.

Defense attorney Joseph Cataldo says “we’re disappointed” with the guilty verdict. Cataldo offered no further comment pending Carter’s sentencing.

Assistant District Attorney Katie Rayburn said there are “no winners” in the case, but that she hopes the decision can provide the Roy family with closure.

“Two families have been torn apart and will be effected by this for years to come,” Rayburn said.

Prosecutors say the then-17-year-old Carter badgered Roy to act on his suicidal thoughts. During the trial, the prosecution showed dozens of text messages to Roy telling him to kill himself.

Defense lawyers argued that Roy had a history of depression and suicide attempts and was determined to take his own life.

Matthew Segal, the legal director of the American Civil Liberties Union of Massachusetts, said that while Roy’s death was a “terrible tragedy,” it was “not a reason to stretch the boundaries of our criminal laws or abandon the protections of our constitution.”

“There is no law in Massachusetts making it a crime to encourage someone, or even to persuade someone, to commit suicide. Yet Ms. Carter has now been convicted of manslaughter, based on the prosecution’s theory that, as a 17-year-old girl, she literally killed Mr. Roy with her words. This conviction exceeds the limits of our criminal laws and violates free speech protections guaranteed by the Massachusetts and U.S. Constitutions,” Segal said.

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“The implications of this conviction go far beyond the tragic circumstances of Mr. Roy’s death. If allowed to stand, Ms. Carter’s conviction could chill important and worthwhile end-of-life discussions between loved across the Commonwealth.”