Two principal sources of imprecision in legal drafting (vagueness and ambiguity) are identified and illustrated. Virtually all of the ambiguity imprecision encountered in legal discourse is ambiguity in the language used to express logical structure, and virtually all of the imprecision resulting is inadvertent. On the other hand, the imprecision encountered in legal writing that results from vagueness is frequently, if not most often, included there deliberately; the drafter has considered it and decided that the vague language best accomplishes the (...) purpose at hand. This paper focuses on the use of some defined terminology for minimizing inadvertent ambiguity in the logical structure of legal discourse, where desired by the drafter. The current set of signaled structural definitions that are included in the A-Hohfeld language are first set forth and their use is illustrated in an extensive example from the treaty establishing the European Economic Community. The use of definitions in legal writing is widespread, butaddressed almost exclusively to controlling the vagueness of substantive legal terms; they are seldom used for structural purposes. Furthermore, their use in American legislative drafting is unsignaled. Here, attention is devoted to the relatively-neglected domain in legal discourse of imprecisely expressed logical structure, and the remedy offered, where desired by the drafter, is a set of signaled structuraldefinitions for use in controlling such imprecision. (shrink)

Different legal expert systems may be incompatible with each other: A user in characterizing the same situation by answering the questions presented in a consultation can be led to contradictory inferences. Such systems can be “synthesized” to help users avoid such contradictions by alerting them that other relevant systems are available to be consulted as they are responding to questions. An example of potentially incompatible, related legal expert systems is presented here ‐ ones for the New Jersey murder statute and (...) the celebrated Quinlan case, along with one way of synthesizing them to avoid such incompatibility. (shrink)