Crime 'Slenderman' Teen Sentenced to 25 Years in Mental Health Hospital for Stabbing Classmate Anissa Weier, who was 12 at the time of the attack, was judged mentally ill when she participated in the 2014 attack on a classmate, also 12 By Jeff Truesdell Published on December 21, 2017 06:47 PM Share Tweet Pin Email One of two Wisconsin teen girls who stabbed a classmate 19 times to appease a fictional Internet bogeyman known as “Slenderman” was sentenced to the maximum 25 years in a psychiatric facility after she was judged not criminally responsible for her actions, according to multiple news reports. Anissa Weier, 15, avoided jail in the sentence handed down Thursday by Waukesha County Circuit Judge Michael Bohren, who gave Weier credit for time she’s already spent in detention dating back to the 2014 crime, FOX News reports. Weir and the second convicted assailant, Morgan Geyser, were both 12 at the time of the attack, as was the victim, Payton Leutner, who survived. “It was a planned murder, by kids,” said Judge Bohren, who followed the prosecution’s recommendation for the maximum sentence, the Milwaukee Journal Sentinel reports. “We can’t forget the goal was to kill.” Michael Sears/Milwaukee Journal-Sentinel/AP In August Weier pleaded guilty to attempted second-degree homicide as a party to a crime with use of a deadly weapon. She was initially charged with attempted first-degree intentional homicide in the stabbing of Leutner. A jury then determined she was mentally ill at the time of the attack. • Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter. Under her sentencing agreement, Weir will not necessarily spend all the time institutionalized but she is required to spend at least three years at the Winnebago Mental Health Institute before she can apply for supervised release which is considered part of the commitment order. Weier has already spent over three years at a juvenile detention center that she is credited for, so the supervision will last until she is 37-years-old. Prosecutors said Weier and Geyser lured Leutner to a park in Waukesha, Wisconsin, after a sleepover and then stabbed her 19 times. Leutner was left to die, but managed to crawl to a bike path where a passerby found her and called 911, according to investigators. Both Weier and Geyser told detectives they felt they had to kill Leutner, the Associated Press reported, in an effort to become Slenderman’s servants — an action that they believed would protect their families from the fictional demon’s wrath. Waukesha Police Department Geyser, who actually did the stabbing, pleaded guilty to the original charge of first-degree intentional homicide filed against both girls, before prosecutors agreed that she was not guilty by reason of mental disease or defect. She was committed to a state mental hospital, after receiving a diagnosis of early onset schizophrenia as part of a court evaluation. • For more compelling true crime coverage, follow our Crime magazine on Flipboard. Prosecutors have requested a maximum sentence of 40 years for Geyser when she is sentenced in February. A letter sent by the victim Leutner’s mother to the judge this week said the attack “has defined our lives,” and the fears that it provoked still linger for her daughter. “She will struggle with the events of that day and physical and emotional scars it left for the rest of her life,” Leutner’s mother wrote.