Judge grants conditional release for Weier in Slenderman stabbing One of the teenagers in the Slender Man case will be allowed a conditional release from a mental institution after a Waukesha County judge's ruling on Thursday. By: TMJ4 Staff and last updated 2021-07-02 17:02:56-04 WAUKESHA, Wisc. â One of the teenagers in the Slenderman case will be allowed a conditional release from a mental institution after a Waukesha County judge's ruling on Thursday. 19-year-old Anissa Weier will serve the rest of her 25-year sentence away from Winnebago Mental Health Institute as long as there are no violations to a plan that has yet to be approved by the court.