This amicus brief by Paul Clement on behalf of the American Beverage Association (the other, other ABA) in POM Wonderful v. Coca-Cola is a masterpiece. The formal legal question -- on which I express no opinion -- is whether a party can bring a suit under the Lanham Act (which governs false advertising) regarding a label of a product regulated under the Food, Drug, and Cosmetic Act. POM's lawsuit accuses Coca-Cola of mislabeling a drink as "Pomegranate Blueberry" juice when it contains just .3% pomegranate juice and .2% blueberry juice (it is 99% apple and grape juice).
And when you put it that way, it sounds really bad! There's an old saying amongst lawyers that when the law is on your side, pound on the law, and when the facts are on your side, pound on the facts (and when neither is on your side, pound on the table). These facts sound very bad for Coca-Cola (99% juices other than the two prominently displayed on the label), so the conventional wisdom would be to bang on the law and downplay the facts.
My theory of advocacy, however, has always been the opposite -- go on offense where your opponent thinks they're strongest. "Offense" is important -- the strategy only works if you argue that the point they think is their ace really, truly, obviously favors your own side. Even if you don't persuade the audience, it has a neutralizing effect -- it makes it seem like the issue is at best a single or a double for the other side rather than they're home run.
I digress. The point I want to make is that Clement starts with what seem to be awful facts, and deftly explains why labeling juices from the perspective of volume may not make a lot of sense. It is clear, lucid, and intuitive -- no small feat given how incongruous the position seems at first glance.
If one is looking for a model of how to write a brief, this is one to do it. It is a masterclass of the art.