Trainers who abuse their horses into performing the artificial high-stepping gait known as the "big lick" will go to great lengths to avoid detection and deny their crimes. We expect this from accused horse sorers, who use painful chemicals and devices on horses' legs and hooves to gain an advantage in competitions. And the existing law to prevent soring has proven ineffective at slowing them down. One case in point is that of Blount County, Tennessee, horse trainer, Larry Wheelon, who faced plentiful and disturbing evidence but managed to walk away scot-free.

The stomach-turning evidence was collected when the Blount County, Tenn., sheriff's office, in conjunction with US Department of Agriculture investigators, searched Wheelon's barn in April 2013. The evidence was enough for a grand jury to indict Wheelon under Tennessee's aggravated cruelty to livestock and conspiracy to commit aggravated cruelty to animals laws – 15 felony charges and three misdemeanors. However, in May 2015, based on a technicality, a Blount County judge granted Wheelon's motion to suppress all evidence obtained during the search.

But while Wheelon may have succeeded in hiding the evidence in his state criminal trial, he can take no cover from the federal Freedom of Information Act. Under this act, The HSUS obtained more than 300 pages of sickening photographs and testimony revealing Wheelon's barn to be a real house of horrors for horses.

Horse soring is the practice of applying caustic chemicals directly to the horses' legs and then tightly wrapping them with plastic wrap and duct tape to cook the harsh substances into the flesh. Then metal chains are placed around the sensitive area, causing excruciating pain with every step. Pain-inducing shoeing methods and barbaric devices are also commonplace soring techniques.

On the day of the raid on Wheelon's barn, it looked like a medieval torture chamber. The walls were lined with heavy logging chains and weighted shoes known as stacks. A shelf was packed with blistering agents, ranging from mustard oil, cinnamon oil and WD-40, to multiple unmarked substances, including one unlabeled jar containing a chemical mixture described by a stable hand as "tea, a powerful concoction of 10 cubic centimeters of cinnamon oil and approximately 200 cubic centimeters of kerosene."

Further evidence photos show horses with weeping open wounds on their ankles, and investigators witnessed chemicals leaking from the wrappings on some horses. Horses are seen standing in a "bucket stance" β€” an unnatural position where they tuck their legs beneath them in a desperate attempt to relieve the pain of simply standing still. One investigator notes, "Three horses were found lying down and moaning at different times of the day."

The investigator further comments: "All of the horses reacted when I touched them with the sample swab. The scars were so inflamed and sore, that I could not get the swab down inside the crevices without the horses raring up."

She goes on: "There was one horse, Broadway Joe that was so sore that when I tried to sample the left foot, he flipped his foot up and caught me with the pad ... Dr. Sutherland attempted to inspect him, but Broadway Joe wouldn't let him get near his left foot."

Based on these photos and reports, I can tell you that if there is a hell on earth for horses, Wheelon's barn on the day of the raid was it. The horses were clearly suffering at the hands of their persecutors.

But Wheelon simply went on with business as usual. He continued to train and exhibit big lick walking horses and to be cited for breaking the law. While under indictment in July 2014, Wheelon was cited and paid a fine for bringing a sored horse to a show. And several of the horses whose soring injuries were so graphically documented in the evidence photos have turned up at shows, including the big lick industry's premier event, the Tennessee Walking Horse National Celebration. In fact, The HSUS recently learned he is demanding the return of his seized soring implements, including a large container of mustard oil.

Sadly, soring of Tennessee walking horses remains rampant despite enforcement efforts by USDA and the work of The HSUS and others to expose and stamp out this cruel and illegal practice. The federal Horse Protection Act sought to put an end to it, but the law has proven too anemic to deter those who are hell-bent on carrying out criminal behavior.

The Prevent All Soring Tactics Act, H.R. 3268/ S. 1121, is the only solution to finally end soring and give these horses the protections they so desperately need. This crucial legislation will amend the existing federal law to end the corrupt system of industry self-policing; ban the use of devices implicated in the practice of soring in Tennessee walking, racking and spotted saddle horses; strengthen penalties and make the act of soring a horse illegal.

Please take action now and urge your representatives in Congress to support the PAST Act.