I've wondered if it would just make you a great consultant as an expert witness. We have one here, and I know he has a practice, but I don't know what he does. Maybe he just does paperwork and other things that don't require court time.
You have to get certified or appointed to be an expert witness. I've met some that are, and some that are not. Most of the ones I met taught pharm law at the nearest COP. One was director of pharmacy at a hospital in western NY making $152K. Some work at health insurance places (MCOs/PPOs/etc.). A few are on the P and T committee at their hospitals. Never met any that were retail