Best bet is a hard science major. If he goes to law school and does well he can do whatever he wants, if he doesn't do well he can always fall back to patent law, which can pay the bills. Law grads who qualify to sit for the patent bar have the easiest time finding good employment post graduation, almost regardless of their grades/ranking.
If he's into business, having a hard science degree and ability to sit the patent bar would also qualify him to be in a pretty unique position in helping start ups, as many need help securing IP early on. That's fun business/law work.