WAUKESHA, Wis. (WITI) — 15-year-old Anissa Weier pleaded guilty on Monday, August 21st to an amended charge of attempted second degree intentional homicide, party to a crime in the so-called Slenderman case.

Anissa Weier is charged along with Morgan Geyser in the attempted murder of their then-sixth grade classmate in the spring of 2014. Investigators say the attack was an attempted sacrifice to the online character Slenderman.

Weier testified during a hearing on Monday and indicated to the court that she understood the amended charge now facing her — and that she admitted to being a party to a crime.

The court accepted Weier’s guilty plea — and she was indeed found guilty of the amended charge. The court then indicated the case would move on to a second phase, where a jury would determine whether Weier is guilty by reason of mental disease or defect.

The court indicated to Weier that the new charge comes with a maximum penalty of 25 years in prison and another 10 years of extended supervision. If Weier were found to be guilty of mental disease or defect, the court said she would be held at a state institution.

Morgan Geyser is due in court in Waukesha County on Monday afternoon. Her trial in this case is set for October.

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