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Benton County man pleads guilty in death of child, abuse of another

Ethan Mast Benton County
Benton County Sheriff's Office
Ethan Mast


One of the four people accused of beating children and killing one of them has admitted to his role in abuse.

Ethan Mast pleaded guilty Tuesday to second-degree murder and first-degree assault. His attorney said he admitted to taking part in the abuse that killed 4-year-old Jessica Mast and hitting a young boy.

Prosecutors claim Mast and a woman he lived with, Kourtney Aumen, abused the children of neighbors James and Mary Mast for a month in late 2020 at their home outside of Cole Camp. That abuse included hitting the children with a wooden spoon and submerging Jessica Mast in a pond during the winter.

The defendants blamed Aumen for leading the abuse, claiming she wanted to keep a "demon" from possessing the girl. James and Mary Mast allegedly told deputies that Aumen and Ethan Mast would unplug security cameras around the house to abuse the couple and their children.

Ethan Mast's attorney, Lacon Smith, said Ethan agreed to testify against the three others at their potential trials. Prosecutors downgraded his original charge of first-degree murder to second-degree murder, and plan on dropping the other felonies at sentencing. Smith said she expected prosecutors to recommend a life sentence for Mast on the murder charge, which state law defines as 30 years in prison. She also expected both sentences for murder and assault to run at the same time. Mast would have to serve 85% of his sentence before he could qualify for parole.

Smith said Ethan took "full responsibility for his conduct," and hoped the other defendants would, as well.

James and Mary Mast both face seven charges including second-degree murder, assault and child abuse. Both have preliminary hearings scheduled for July 1. Aumen's case was moved to Webster County in January.

Article Topic Follows: Crime

Lucas Geisler

Lucas Geisler anchors the 5 p.m. show for ABC 17 News and reports on the latest news around mid-Missouri at 9 and 10 p.m.


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