Massachusetts Teen Fights Involuntary Manslaughter Charge in Boyfriend’s Suicide Prosecutors say Michelle Carter, 18, encouraged her boyfriend to kill himself.

 -- A teenager from Massachusetts could be one step closer to standing trial for allegedly convincing her 18-year-old boyfriend to commit suicide.

Michelle Carter, 18, whom prosecutors accuse of encouraging her boyfriend to kill himself in text messages, is appealing her involuntary manslaughter charge in his death while a judge moves both sides towards a trial.

Carter’s boyfriend, Conrad Roy, died of carbon monoxide poisoning in July 2014 after locking himself inside his truck in a Kmart parking lot.

Prosecutors say that Roy was on the phone with Carter for 47 minutes while in his truck, at one point telling her he was getting out of the truck because he feared the suicide attempt was working.

Just days before, in another text message, Carter wrote “don’t be scared… You’re finally to be happy in heaven," according to prosecutors.

The couple met in 2012 while visiting relatives in Florida but lived 50 miles apart in Massachusetts. Roy and Carter communicated mostly through text messages and email and had not seen each other for nearly a year before Roy committed suicide.

Roy’s great-aunt, Claudette Roy-Viaol, told media outside court in August 2015 she didn’t understand Carter's alleged text messages.

“It’s inconceivable,” she said. “I just don’t understand how someone could do that, to encourage someone they claimed to love.”

Roy had attempted suicide and had been hospitalized before he met Carter, according to court documents.

In one text message two weeks before his suicide, he expressed his desire to take his own life, writing, “I can’t get better, I already made my decision.”

The defense is now trying for a second time to have the involuntary manslaughter charge dropped, with an appeal filed two months ago that is still pending.

In the appeal, Carter’s attorney, Joseph P. Cataldo, argues that Conrad Roy had made up his own mind about taking his life and convinced Carter of his decision.

“He has in fact brainwashed her to the point where she’s now accepting his idea of this is my only option,” Cataldo, told reporters outside court last August.

In a statement to ABC News, Cataldo wrote that, “Michelle’s communications were by no means threatening” and that Roy “made his own conscious decision to take his own life,” adding “this is a tragedy, not a crime.”

ABC News' legal analyst Dan Abrams spoke about the case today on “Good Morning America."

"This is not an easy case for prosecutors. They are going to have to show that she caused his death," Abrams said. "If there was an assisted suicide ban in Massachusetts, the way they are in more than half the states, it would be much easier. They’d just be able to prove she helped, she encouraged, she assisted; they don’t have that kind of law in Massachusetts.”

“It’s possible a court will throw it out," Abrams added.

Carter faces up to 20 years in prison if convicted. She is being tried as a youthful offender, a status that allows harsher punishments than typical juvenile cases and allows for court files to be open to public inspections.

Editor’s Note: This article has been updated to correct the date Carter and Roy met, it was 2012. It was also edited to correct what prosecutors say was Roy’s state of mind in the last moments of his life.