Prosecutors are charging a Massachusetts teen with involuntary manslaughter in her friend's suicide.

Bryan Llenas reported on "America's News Headquarters" that last summer Conrad Roy, 18, was found in his truck behind a Kmart in Fairhaven, Massachusetts, dead from carbon monoxide poisoning.

Llenas reported that when police searched Roy's phone, they found more than 1,000 text messages with Michelle Carter, 18.

According to court documents obtained by the Fairhaven Neighborhood News, the texts show that Carter helped Roy choose his method of suicide, Llenas said.

Llenas said that in the act of committing suicide, Roy texted Carter to say that he was scared and didn't want to leave his family.

"But still, prosecutors say, she encouraged him to go through with it," Llenas reported. "At one point, Conrad got out of the truck, [to] which Michelle replied, get back in."

Gregg Miliote, of the Bristol County District Attorney's Office, said, "Instead of attempting to assist him or notify a school official, a counselor, a family member, anyone, Ms. Carter is alleged to have strongly influenced his decision to take his own life."

Carter's defense attorney Joseph Cataldo said, "This is a case where a young man made his own voluntary decision. It was not a death caused by Michelle Carter. It was a suicide, not a homicide. Mr. Roy had a history of wanting to take his own life and he finally accomplished that, and he did that in his own free will."

Carter was 17 at the time and is being charged as a juvenile.

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