Language teachers talk about translators' "false friends" -- words in a foreign language that sound familiar, but are quite different. The classic example is the Spanish "embarazada," which does not mean embarrassed. Likewise, the Russian "magazin" means a shop, not a magazine (the latter translates as "zhoornal," cognate to journal).
I'm looking for examples of the legal historian's false friends -- terms (mostly English terms) that might sound familiar to a law student doing legal research today, but really mean something different from what the student would at first expect.
I've seen this, for instance, in my Second Amendment work. "Militia," for instance, pretty clearly meant something like "the armed able-bodied citizenry" (limiting citizens to first-class citizens of the time, and excluding blacks, Indians, and women) rather than "National-Guard-like force" or "small military band," which is what many people tend to think of when they hear "militia" today. Likewise, "free State" meant not "state independent of the federal government" but something like "democracy, republic, or constitutional monarchy" as opposed to a despotism. Neither of these terms have entirely lost the old meaning; but they have acquired enough of a modern meaning that the modern meaning may lead modern readers astray. Dean William Treanor points to another example, here of a change in grammatical convention:
Justice Thomas, Professor Amar, and others have assigned critical interpretive weight to the fact that, to quote Justice Thomas, "[i]n the Constitution, after all, 'the United States' is consistently a plural noun." This grammar would appear to suggest, as Justice Thomas and Amar have concluded, that the Constitution, as initially adopted, reflected the view that the United States was a collection of states, rather than one nation. What this reading misses, however, is the fact that, in the late eighteenth century nouns ending in "s" were commonly assigned plural verbs, regardless of whether the noun itself was plural or not, a rule gradually displaced as the nineteenth century progressed. It is true that "United States" was often matched with a plural verb in 1787 and consistently matched with a singular verb after the Civil War. But one cannot conclude simply from this change in grammatical practice that the dominant political theory changed, since the same verb shift occurred for the word "news," and there was no reconceptualization of "news."
(I can't personally vouch for the accuracy of this argument, but my sense is that Dean Treanor enjoys a very good reputation as a historian; and, more broadly, this is an example of the sort of thing I'm looking for, even if some might disagree with Dean Treanor's particular argument.)
Any suggestions? Please pass them along.