Briar was found injured with a gunshot wound in his back early the morning of Jan. 12 on County Road 125 West in Jay County, according to court records.
He was pronounced dead later that day at Lutheran Hospital in Fort Wayne.
Preliminary autopsy results indicate Briar died from a gunshot wound, according to court documents.
During interviews with investigators, Hiestand and Stephen reportedly admitted to conspiring to kill Briar.
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“Esther Jane Stephen was angry with Shea Briar because [he] had recently initiated court proceedings to establish parenting time rights for their minor child and petitioned the court to change the child’s last name,” according to court records.
Jay County Sheriff’s deputies arrested Stephen and Hiestand in Indiana on Tuesday.
They are being held without bond at the Jay County Security Center, according to the prosecutor's office.
Fort Recovery Local Schools have relieved Stephen and Hiestand of their coaching duties until further notice.
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Stephen is the high school’s head softball coach and Hiestand is the assistant coach.
They are on administrative leave pending further investigation by law enforcement, according to a Facebook post the district shared Tuesday.
The women are not allowed on district property without written permission from the superintendent.