TAUNTON — A Massachusetts teenager accused of sending her friend text messages encouraging him to kill himself is due in court for a pretrial hearing.

Michelle Carter is charged with manslaughter in the 2014 death of Conrad Roy III. The 18-year-old Roy died of carbon monoxide poisoning. Prosecutors say the then-17-year-old Carter had sent him dozens of messages urging him to follow through on his suicide plan.

Earlier this month, Carter’s attorney asked a judge for funds to hire an expert to explain the effects of an antidepressant to a jury at Carter’s trial. The judge denied the request.