Key evidence missing in a criminal case has been found. Investigators don't know if it walked away or someone took it.

Scotchy would’ve been at risk 150 years ago when horse thieves roamed the plains. "This is the horse that brought down the last known slaughterhouse in the U.S."

Last November, Linda Belsky-Lohr took in Scotchy and four other horses and brought them to her Yutan, Nebraska farm. "I need to move these horses quickly, there's a threat against their lives."

She says they were involved in an out-of-state animal abuse case. "We don't know why he was beaten, but he was beaten with a bat on the right side of his head. The vet in Pennsylvania felt that it would abscess into the brain so he took the eye."

Last Wednesday, no one could find the 5-year-old Belgian. Scotchy had disappeared. "He is still evidence, but a horse that's missing or that you can't find is no longer evidence."

Scotchy was found three-and-a-half miles from his home, eating apples and chips from residents. His owner wants to know what happened because if he wandered out on his own, the terrain he would have covered would have left cuts all over, but he didn't have any.

"He's blind, he can't see," says Belsky-Lohr. "We brought him home and put him in his stall and the first thing he did was bang his head against the wall."

With Scotchy now safe, his owner had taken precautions to guard against her theory from happening again. "Someone took him, walked him out of the property and panicked when the plot was uncovered and they dropped him off. That's one of the theories."

According to the Humane Society of the United States, 95,000 American horses were killed last year in Canadian and Mexican slaughterhouses. Since the last known slaughterhouse for horses in the U.S. has closed, more and more horses are being exported.