Interesting 1686 law that was found. However, one of the issues not discussed in the Ammo Land summary was one state’s ability to interfere with interstate commerce.
If a businessman transporting valuable products or cash that could be stolen is crossing a state border in the course of his/her business the Massachusetts law might be an impediment to interstate commerce, which is reserved for the federal government to regulate.
Though I believe that the principal issue here is individual, specifically a second amendment right, I think that you are correct that there is a possible impact on interstate commerce. Perhaps not in this particular case, but in a general sense. I don’t think there would have been any harm whatsoever if the accused had raised this issue at the lowest level. By failing to do so, I believe that he is now precluded from raising it at a higher level. That was, in my opinion, a very big mistake. Raise the issue, and if it has no merit then a court will throw it out, and you can litigate at the next level whether that was proper or not. You raise every single issue that you possibly can, on the theory that if you don’t win in one place, you may in another