HPA Basics:
The HPA is found in 15 U.S. Code Secs. 1821-1831. Go here to read it https://www.law.cornell.edu/uscode/text/15/chapter-44
To what horses does it apply:
Sec. 1822:
The Congress finds and declares that—
(1) the soring of horses is cruel and inhumane;
(2) horses shown or exhibited which are sore, where such soreness improves the performance of such horse, compete unfairly with horses which are not sore;
(3) the movement, showing, exhibition, or sale of sore horses in intrastate commerce adversely affects and burdens interstate and foreign commerce;
(4) all horses which are subject to regulation under this chapter are either in interstate or foreign commerce or substantially affect such commerce; and
(5) regulation under this chapter by the Secretary is appropriate to prevent and eliminate burdens upon commerce and to effectively regulate commerce.
All horses are subject to the Act, but only those horses which are sored to improve performance are regulated. As a practical matter this means Walking, Racking, and Spotted Saddle Horses. If other breeds begin using practices prohibited by the Act they, too, can be regulated.
“Sore” horses are prohibited. What does “sore” mean? It means this:
Sec. 1821
(3) The term “sore” when used to describe a horse means that—
(A) an irritating or blistering agent has been applied, internally or externally, by a person to any limb of a horse,
(B) any burn, cut, or laceration has been inflicted by a person on any limb of a horse,
© any tack, nail, screw, or chemical agent has been injected by a person into or used by a person on any limb of a horse, or
(D) any other substance or device has been used by a person on any limb of a horse or a person has engaged in a practice involving a horse, and, as a result of such application, infliction, injection, use, or practice, such horse suffers, or can reasonably be expected to suffer, physical pain or distress, inflammation, or lameness when walking, trotting, or otherwise moving, except that such term does not include such an application, infliction, injection, use, or practice in connection with the therapeutic treatment of a horse by or under the supervision of a person licensed to practice veterinary medicine in the State in which such treatment was given.
If a pad, chain, or other prohibited device is used to “improve performance” then that triggers the protection of the act to the horse. That includes trotting horses.
The is an entire section of Code of Federal Regulations (44 FR 25179) that create the enforcement mechanism for the HPA.
In short: It applies to all horses that are sored to improve performance, including trotting horses. Since, as a practical matter, soring of a trotter would degrade vice improve performance they are not part of the present regulatory system. If somebody comes up with a way to “sore” a trotter to make it “better” then they will get a visit from APHIS.
G.
