Morgan Geyser and her friend Anissa Weier had stabbed classmate Payton Leutner 19 times in 2014
A US teen who pleaded guilty to trying to kill a friend to appease a fictitious internet character was sentenced to 25 years in mental hospital by a judge on Thursday.
Anissa Weier and her friend Morgan Geyser were both 12-years-old when they stabbed classmate Payton Leutner 19 times in 2014, because they wanted to appease Slender Man, a sinister internet meme often inserted into the background of ominous black-and-white photos.
Now 15, Weier, who was sentenced Thursday, and Geyser offered insanity defenses and said they believed that Slender Man would hurt their families if they did not meet his demands.
Geyser has also pleaded guilty and is already receiving treatment at a mental hospital. She is awaiting a sentencing decision in February.
Leutner survived and crawled out of the wooded area where she had been left.
Weier's sentence, which will be applied retroactively to when she was first arrested, would keep her in custody until she is 37.
But she could also be released earlier under court supervision, if doctors believe she is well enough.
"I just want everyone involved in this to know that I do hold myself accountable for this," Weier told Judge Michael Bohren before he handed down the sentence.
"I will do whatever I have to do to make sure I don't get any sort of delusion or whatever again. And I want everybody involved to know that I deeply regret what happened that day," she added.
But the judge sided with prosecutors in handing down the maximum sentence, saying he was concerned that a medical report indicated Weier was still having delusions while in custody, which "leads the court to be concerned about a short commitment period."
"I'm satisfied that a 25-year commitment is appropriate," the judge said. "It gives the community assurance of safety and protection."
The case has been the subject of public fascination, with video of the girls' police interrogations featured in the 2016 HBO documentary "Beware the Slenderman."
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