Judge refuses to unseal documents in high school murder plot

A judge has refused to unseal details in the case of two 16-year-old girls accused of conspiring to kill students at their suburban Denver high school.

Douglas County District Judge Paul King said Wednesday it would be premature to release documents in the case against 16-year-old Sienna Johnson. Prosecutors have charged her as an adult with conspiracy to commit first-degree murder. But her case could be returned to juvenile court at the urging of her defense attorney.

Prosecutors are set to decide Thursday whether to charge the other girl as an adult.

Prosecutors say Johnson bought a BB gun for practice and mapped out plans to attack Mountain Vista High School in Highlands Ranch. The other girl’s attorney says the two were not close friends and their cases are different.