The Volokh Conspiracy
Mostly law professors | Sometimes contrarian | Often libertarian | Always independent
I just came across the phrase "libel of information" for the first time, and had to look it up. In case you were as ignorant of this as I was, the answer offered by Black's Law Dictionary is:
The complaint or initial pleading in an admiralty or ecclesiastical case.
But as best I can tell from glancing at some of the cases that use the term, it also more generally refers to the initial pleadings in a civil forfeiture case. The term is pretty common in old cases and even appears in some current statutes; but it has recently fallen, as they say, into desuetude—a Westlaw query uncovers only 4 references since 2000.
Now you know, and knowing is half the battle.