The Springfield News-Sun reports Clark County Juvenile Judge Katrine Lancaster made the determination involving the 15-year-old and 13-year-old girls Tuesday. It followed her review of a competency evaluation conducted by a local psychologist.
The teens both face the juvenile equivalent of murder and felonious assault charges in the May 23 attack. The 13-year-old's father and teen brother also were wounded.
Authorities say the girls conspired after the 13-year-old's parents told her she couldn't meet with the friend anymore.
The county prosecutor has asked to move the case against the 15-year-old to adult court. The 13-year-old can't be tried as an adult because of her age.
Both have pleaded not guilty.
Information from: Springfield News-Sun, http://www.springfieldnewssun.com
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