The Mischief Rule, an article on statutory interpretation that I published several years ago, begins this way:
A Tennessee statute imposed duties on railroad engineers. If a railroad engineer found an animal or obstruction on the tracks, the statute required "the alarm whistle to be sounded, and brakes put down, and every possible means employed to stop the train and prevent an accident." But what counted as an "animal" on the tracks? Cows and horses, yes. But what else? Did all the trains in Tennessee have to stop for squirrels?
The stop-the-train case poses difficult questions for some interpretive theories, especially textualism. The text does not identify a stopping point in what counts as an animal. Nor is there a dictionary definition that will include cows but exclude squirrels. Is a textualist interpreter duty bound to say that trains really do have to stop for squirrels?
Note that there is no dictionary definition for animal that will mean "sizable animal," or "animal of the sort you would need to stop a train for." If you are willing to look at context, including the mischief, but only if you can first find some ambiguity, then you will be absolutely flummoxed by the stop-the-train statute. The solution, or so I argue in The Mischief Rule, is that interpreters should consider the mischief as an aspect of context not only after concluding that a statute is ambiguous, but also when deciding whether it is ambiguous in the first place.
