Teen Allegedly Goaded Into Suicide by Girlfriend Took 20 Minutes to Die: Medical Examiner

It was implied that Michelle Carter would have had plenty of time to call police as her boyfriend Conrad Roy died of carbon monoxide poisoning.

It appears that a young woman accused of encouraging her boyfriend to suicide would have had plenty of time to save his life after a medical examiner testified Thursday that it took the teen about 20 minutes to die. 

Michelle Carter, who is charged with involuntary manslaughter, was on her phone with Conrad Roy III as he killed himself in 2014 by allowing carbon monoxide to fill his grandfather's truck in a Massachusetts parking lot.

Read: Court Hears Text Messages From Woman Accused of Urging Boyfriend to Kill Himself: 'It's Time, Babe'

The windows were closed in the vehicle, and in the back seat were a gas-fueled generator and a can of starting fluid to get the generator going.

The Boston Globe reported that Medical Examiner Dr. Faryl Sandler took to the stand Thursday, saying that a person exposed to carbon monoxide would begin coughing after a few minutes before falling unconscious after 13. Their heart rate would then continue slowing down until death.

It takes on average, 20 minutes for someone to pass due to carbon monoxide poisoning, according to the medical examiner, which supported the prosecution's argument that emergency personnel could have gotten to Roy before his death.

On Wednesday, Carter, surrounded by her attorneys, went to the Kmart parking lot where Roy died. The judge presiding over her case, which is being heard without a jury, was also in attendance.

Text messages sent by Carter to her boyfriend appear to encourage the teen to kill himself.

“You're ready and prepared. All you have to do is turn the generator on and you will be free and happy,” she texted him. “No more pushing it off. No more waiting.”

Four of Carter's girlfriends took the stand at her trial, reading chilling text messages she sent them after Roy took his life.

His death is my fault, like, honestly. I could have stopped him, I was on the phone and he got out of the car because it was working and he got scared and I f***ing told him to get back in,” one of the messages read.

The prosecution is painting Carter as an attention-seeker and drama queen who pushed her boyfriend over the edge so that she could be seen as "the grieving girlfriend."

Read: Principal's Suicide in School Parking Lot Came Amid Adultery Allegations, Officials Say

She even hosted a baseball game fundraiser called "Homers for Conrad" smiled wide while posing for photos.

A haunting video of Roy, recorded just one month before his death, is also among the evidence. In it, he discusses his struggle to overcome depression.

“The hardest thing for me is to be comfortable in my own skin," he says in the video. "A lot of people tell me I have a lot going for me. I have to be happy. I have to be happy."

The defense has argued that Roy is responsible for taking his own life, arguing that he was depressed and he tried to commit suicide in 2012.

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