On Feb. 1, Aidan Zellmer pleaded guilty to the murder charge and, in exchange, other charges were dropped. Zellmer was 15 when he was formally charged with four counts of murder and three counts of sexual assault in connection with the death of Kiaya.
She was reported missing on June 7, 2017. At the time, her family told police that she and Zellmer had left a home in the 12400 block of Forest Drive in Thornton to walk to a nearby shopping center – then became separated in a rainstorm.
According to a warrantless arrest affidavit for Zellmer, he and Kiaya were going to steal Pokémon cards from a King Soopers on 120th Avenue and Colorado Boulevard around 7:30 p.m. They returned empty-handed around 8 p.m. and headed out, this time with a backpack and water bottles.
Kiaya was never seen again.
According to the affidavit, Zellmer wasn't seen again until his step-dad found him around 1 a.m. He said he'd lost Kiaya while walking and that he'd been searching for her for hours, the affidavit said.
The next afternoon, while Zellmer was in the middle of a break during an interview with the Colorado Bureau of Investigation, Kiaya's body was found.
Kiaya's body was found in a natural area in Thornton in the area of 128th Avenue and Jasmine Street. As soon as he was told her body had been found, Zellmer became "inconsolable," according to the affidavit, and kept saying "I didn't hurt her, I left her." According to the report, Zellmer tried to say he'd just left her while walking behind a Walmart in a neighborhood she didn't know because she was being "annoying."
Kiaya was killed by blunt force trauma to the head, according to an autopsy done by the Adams County Coroner's Office and cited in Zellmer's arrest affidavit. She was hit in the head five times, which caused several skull fractures. She had bruises and abrasions to other parts of her body, which included defensive wounds.
Kiaya's body was found face-down on the ground, nude from the waist down, the warrantless affidavit said.
Officers had requested the clothes Zellmer was wearing at the time of Kiaya's disappearance and tested them after Kiaya's body was found. A serological test on his shoes found blood. He was arrested after a DNA match was found and taken to the Adams County Juvenile Detention Center.
Because the sexual assault charges were dropped, Zellmer is eligible to participate in a youth corrective program. If he's a model inmate and makes it through that program, he could get out at age 47.
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