We all know what "faulty tack" means. It is saddles and bridles and girths and stirrup leathers that are broken or so old and decrepit that they are about to break. Faulty tack is unsafe tack. In Maine, though, thanks to a federal district court judge, "faulty tack" may have an entirely different meaning.

Forty-six states have some sort of equine activity law that can be raised as a defense in a personal injury lawsuit by individuals who put on horse shows, competitions, and other events. The idea behind these laws is that some things associated with working around horses, such as falling off or being kicked, bitten, or stepped on, are so closely associated with the activity that participants should accept those risks. An event organizer is required to warn participants about these "inherent risks," but they are not required to eliminate them. This is the genesis of the ubiquitous warning signs that show up on farms and at competitions.

Equine activity laws are not an absolute defense against a personal injury lawsuit. There are some exceptions, including negligent acts of the event organizers or their employees. The theory is that a participant should anticipate the possibility of being kicked by a horse, but should not be required to assume the risk of a negligent employee.

Most equine activity laws also exclude injuries that result from faulty tack provided by the event organizer. This makes sense, too, because an event participant should not have to assume the risk of tack that is not up to snuff.

But when, exactly, is tack "faulty?"

There should be little argument that tack is faulty when it is too old or worn to be safe, when it is dry and cracked, or when it is weakened or defective in some other way. A federal district court in Maine now has opened the door to an extension of the definition of "faulty" to include tack that is serviceably sound but that is used in an inappropriate manner. This definition could create another exception to most states’ equine activity statutes and put stable owners at additional risk for personal injury lawsuits.

The question arose after a young girl was injured during a riding lesson on Tinkerbell, a fat, round pony with low withers. It apparently was difficult to keep a saddle secure on Tinkerbell, and a crupper always was used to help keep the saddle in place. The stable also used a fleece-lined girth cover on Tinkerbell and its other lesson horses.

There were different versions of what actually happened. The injured girl’s family claimed that the saddle slipped. The stable owners said that the girl simply lost her balance and fell off. They also argued that even if the saddle had slipped it was an inherent risk associated with riding. If that were true, the Maine equine activity law applied.

The injured girl’s family never claimed that the tack used on Tinkerbell was defective. Instead, they argued that the stable owners made what the court called a " ‘faulty’ tack decision" in three ways: by failing to tighten the girth, by using a fleece-lined girth that was more likely to slip, and by using a pony that was too fat to be saddled safely for lessons.

The judge determined that the word "faulty" in the Maine statute was "sufficiently ambiguous to include the use of non-defective but inappropriate equipment." Faulty tack, in other words, could be tack that was defective, or it could be serviceable tack that was used in an inappropriate manner.

The question of how to define "faulty tack" came up in the stable’s motion for summary judgment. This is a request by one of the parties to a lawsuit asking the judge to decide the case before a trial because the other side cannot win as a matter of law. The judge denied the stable’s motion and ruled that the definition of "faulty tack" was a question for a jury.

Using serviceable tack in an inappropriate or dangerous manner sounds a lot like negligence, which already is an exclusion in most states’ equine activity laws. It does not sound at all like the generally accepted definition of "faulty tack."

One of the things that makes the study of law interesting—and, not coincidently, keeps hordes of lawyers in business—is a simple fact: Figuring out what a legal term actually means is never as easy as it looks.