Challenge to felon in possession turned back
There's a discussion of a 6th Circuit case, rejecting a challenge to prohibited person prosections as "selective prosecution" based on race, over at the Volokh Conspiracy
The debate reflects a problem that often occurs: (1) if you allow a challenge to be made, and discovery to be obtained, based on little evidence, you'll spend a lot of time sorting out those challenges and (2) if you require the defendant to come up with the evidence without discovery, odds are no challenge will ever be made. Courts in that situation tend to go with (2). Maybe I'm cynical, but the fact that (2) entails less work for the judiciary may play a role.