I would think that since 922(o) is based on the commerce clause, a tax attorney would probably be best suited, no?
If a tax attorney was best suited, then it would have been wise to retain one prior to your arrest for a discussion of your legal strategy. Retaining counsel after you have already been arrested is typical of the type of Second Amendment challenges that have given us very bad precedent in the past.
For example, in the Eighth Circuit (where this case will be heard), we have
United States v. Hale, 978 F.2d 1016 (8th Cir. 1992)
cert. denied which reached the decision that "Considering this history, we cannot conclude that the Second Amendment protects the individual possession of military weapons." This same decision is repeated in about five other Eighth Circuit cases. SCOTUS denied cert in every one of those cases. Hale was also in a "militia" so it is pretty much on point for the Eighth Circuit.
So unless the Eighth Circuit decides to overturn their previous six rulings over the past 30 years, Fincher is going to lose at the District Court level and he will lose again at the Circuit Court of Appeals level. His one small chance is that the Eight Circuit will say something in their decision that his attorney can use to convince the Supreme Court to grant cert here where it was denied every other time.
Stilley may be a courageous, tenacious lawyer who never gives up; but I don't see anything in the cases that I have found that suggests to me he has the talent necessary to pull off the minor miracle I just outlined above. He would need considerable skill to pull it off as part of a planned legal assault on the collective rights theory. To pull it off after his client has already been arrested and the facts of the case set in stone, well... he will need to be much, much better than his current track record against the government indicates.
There are two ways that noncompliance with unjust laws works - one is by clogging the systems with more people than it can process. Currently, not a lot of people are attempting this method. The second way it works is to create
favorable precedent to help change the law. This case will certainly create more precedent; but the chance that it is favorable to an individual rights interpretation of the Second Amendment is a decidedly small one. About the best thing I can say for it, is that there is almost no chance it will get to SCOTUS, so the bad precedent it creates will be limited to the Eighth Circuit where it won't change much since there is already plenty of bad precedent.