Sheriff's deputies were told by witnesses that Casteel backed over her mother, Mary Jane Donn, 56, as Donn sat in a plastic chair in the driveway of a home where relatives had gathered, according to an arrest affidavit.
Casteel's sister, Michelle, told the deputies that Casteel thought her Chevrolet Blazer was in drive, not reverse, according to the affidavit.
Witness Michael Carey, who was named in the affidavit, said the group was at his house. He said people in the yard yelled "You killed grandma" at Casteel. Casteel got out of her SUV, checked on her mother, said she was breathing and drove off, the affidavit said.
Donn was taken to a hospital and pronounced dead.
Casteel later returned to the house but was blocked by deputies when she tried to turn around and leave at the sight of their cruisers. The affidavit said a breath test showed Casteel had a blood-alcohol content of 0.243 percent.
Casteel didn't have a listed phone number. A clerk at Hot Springs District Court, where Casteel has a July 8 appearance scheduled, said no attorney was listed for her. The Garland County jail did not have information on whether Casteel has an attorney.
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