Investigators want her charged with animal cruelty, and on Thursday they handed over their findings to the Snohomish County prosecutor.
Two months after she was rescued, Monica Carlile has nursed "Whisper" back to health.
The investigation began after a concerned neighbor reported the extreme case of horse neglect to animal control officers about two months ago.
Officers went to the woman's property and found Whisper, a 2-year-old filly Pinto, near death. She was skin and bones.
Police say her former owner didn't feed her. Whisper was listless and could barely stand.
Her backbone, hips and ribs protruded. Her coat was matted down with mud and her body was covered in bloody sores.
Today Whisper is a new horse. She's gained weight and her ribs and hips are no longer protruding. She's standing tall and her coat has a glossy sheen.
"There were many moments where I thought she wasn't gonna make it," said Jaime Taft, president and founder of SAFE (Save a Forgotten Equine), a Snohomish County rescue haven for horses took Whisper in.
Whisper was so emaciated she collapsed shortly after being rescued. The only way Whisper could stand up was by lifting her with a custom-made harness. Three weeks of around-the-clock volunteer care did it.
A vet with Evergreen Holistic Veterinary Care donated countless hours of care, and our Problem Solver viewers helped, too, by sending in donations of money and feed.
"It was tough. I think the reason we kept going is because she was not ready to go," said Taft.
Whisper had things to say. The moment our photographer zoomed in for a close-up Whisper responded with a booming "neigh."
And once the harness came off and the pasture gate opened, Whisper - who couldn't stand on her own just a month ago - went from trotting to galloping in a matter of minutes.
She has a roommate now - another rescued horse named Wishes. Both horses recently moved in with a foster family, Bryan and Monica Carlile of Sultan who have instantly bonded with Whisper.
"She's special, she's ..." fighting back tears, Monica Carlile struggles to finish her sentence, "Any horse that is that willing to forgive people deserves ..."
A second chance at life ...
"She's had a lot of unkindness and unjust done to her, and she still loves people," said Carlile.
The Snohomish Police Department says the horses' owner could face charges of animal cruelty.
Whisper will eventually need a permanent home, but needs time to gain more weight and adjust to her foster family.