Lawyers, what's the most obscure law that you've actually used in a case?

As long as we're talking about obscure cases and bird law, Geer v. Connecticut, 161 U.S. 519 (1896) from the US Supreme Court is a fun read. Here's a highlight for you:

The Roman law, as stated in the Digest, cited in the opinion of the majority, expresses it as follows: "That which belongs to nobody is acquired by the natural law by the person who first possesses it." A bird may fly at such height as to be beyond the reach of man or his skill, and no one can then assert any right of property in such bird; it cannot, then, be said to belong to anyone. But when, from any cause, the bird is brought within the reach and control or use of man, it becomes at that instant his property, and may be an article of commerce between him and citizens of the same or of other states.

/r/AskReddit Thread Parent