When a ship goes down, who gets the salvage? If you find sunken treasure at sea, can you keep it?
I honestly have no idea what the answer is to either of those questions, but a lawyer who practices maritime law probably does. It might surprise you to learn that the law of the sea is actually quite complex and can involve the claims and laws of different countries, depending on the details of territorial waters, flagging of ships, or the nationality of the parties involved.
Veterans with an interest in the sea (and I hear there are two entire services for that kind of thing 😉 might consider swapping out coveralls and BAH for a three-piece suit and a boat-load of money as a lawyer specializing in maritime law.
Also, before you get too excited, I should mention that maritime law is distinct and unrelated to the pirate code (which is really more like guidelines anyway), so expect to see more legal briefs than swashbuckling adventure should you choose to go down this career path.