SPRINGFIELD, Mo. – A Missouri woman has admitted that she plotted with her mother to fatally poison her brother and father using antifreeze, and that she attempted to kill her sister the same way.
Rachel Staudte, 24, on Tuesday pleaded guilty to second-degree murder and agreed to testify against her mother, Diane, in the April 2012 death of her father, Mark, and the September 2012 death of her brother, Shaun.
Staudte, of Springfield, also admitted to one count of armed criminal action and one count of first-degree assault in the 2013 poisoning of her sister, Sarah, who survived.
Under the terms of the plea agreement, Staudte will serve two concurrent life sentences for the killings and a 20-year term for the other charges.
Her mother's trial is scheduled for November and prosecutors have said they will seek the death penalty.
Diane and Rachel Staudte's attorneys and Todd Myers, chief assistant Greene County prosecutor, didn't immediately return phone calls from The Associated Press seeking comment.
According to the probable cause statement, Diane Staudte told investigators that she poisoned her 61-year-old husband with antifreeze because she hated him, and that she killed her 26-year-old son because he was "worse than a pest." She also admitted poisoning Sarah Staudte over four days because "she would not get a job and had student loans that had to be paid," investigators said.
The medical examiner in Greene County at first ruled that the husband died of natural causes and the son died as a result of prior medical issues. But an anonymous tip led authorities to re-examine the deaths after the hospitalization of Sarah Staudte, who was then 24, the statement said.
Diane Staudte admitted under questioning to poisoning her family by putting antifreeze in their soda and Gatorade over several days, the statement said.
The probable cause statement in Rachel Staudte's case, said Diane Staudte originally told police she was the only one involved. But the statement said that when Rachel Staudte was confronted with evidence, she admitted to taking part in the deaths and assault. During a subsequent interview, Diane Staudte then admitted that she and Rachel Staudte had planned, researched and committed the crimes together, the statement said.
The Springfield News-Leader reported that the plea agreement says Rachel did not want to poison Shaun and Sarah, but she did so because of her mother's instructions.
A poem that was found in Rachel Staudte's purse when she was arrested was read during the sentencing. It ended with the line: "Only the quiet ones will be left, my mother, my little sister and me."