Roger Shuy at the Log has a post about the legal use of inure, which the OED defines as “To come into operation; to operate; to be operative; to take or have effect,” used in the context of something being for someone’s benefit:
1651 G. W. tr. Cowel’s Inst. 137 This Legacy shall inure not only to A. but to B. and his Heires also.
1879 PARKMAN La Salle 92 The results.. were to inure, not to the profit of the producers, but to the building of churches.
Shuy’s example is from the Montana Department of Revenue: “No part of the net income of a Montana tax-exempt organization can inure to the benefit of any private stockholder or individual.” As he points out, this is confusing to non-lawyers, since everybody else is familiar with it only in the context of getting used to something bad:
1781 COWPER Hope 7 The poor, inured to drudgery and distress.
I challenged the use of inure in this letter, but the lawyers in the tax department strongly objected. I argued that these tax letters are replacing a word with one meaning that lay people know with a word that has another meaning known only to lawyers (probably) and accountants (possibly). But the lawyers informed me that inure is one of those magical words that is absolutely necessary for legal reasons.
The other usage that caught me by surprise recently is an odd use of the verb trespass. You might not think it’s a transitive verb, and if you accept that it could be used transitively you might think only laws and the like could be trespassed, but these days it’s said of people; the best explanation I’ve found is in Charles A. Sennewald’s Shoplifters Vs. Retailers (New Century Press, 2000):
Some stores will “trespass” a person caught shoplifting. … To be “trespassed” simply means the customer has become a “persona non grata,” a person not wanted.
I can’t say I care for it, but the English language doesn’t seek my approval before moving on. I’m not sure if this is used by lawyers or only by security personnel, and I also don’t know how far back it goes. It doesn’t seem to have reached the dictionaries yet.