Briefly, lawyers are experts in identifying the meaning of language in legal context; historians are not and, to their credit, don’t even try (unless they are submitting amicus briefs to the Supreme Court). In addition to describing past events, historians are particularly interested in explaining why what happened in the past happened, why people did what they did; as a result, they are very concerned with identifying motives, or other causal influences. Historians have no particular interest in the meaning of authoritative legal texts, unless they are legal historians who are very often also lawyers. The fact that a legal text is old sometimes makes the identification of meaning more difficult, but far from impossible in most cases. For one thing, the meaning of language hasn’t changed that much.
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