Yet another author fails to note that no one showed up to argue Millers side, that is why the court couldn't say that a short shotgun could be a militia weapon. I think that is important info.
Even more important is the fact that neither Miller nor co-defendant Layton was ever convicted on the short-barreled shotgun charges! Miller happened to be dead at the time, but the government offered Layton a plea-bargain for "time served" rather than go to court. Had the government gone to court, Layton would have been allowed to produce evidence that sawed-off shotguns are militarily useful, and if a jury found that they were (likely, given that Layton could show that such weapons were used in World War I) the jury would have had to acquit.
Can anyone think of any other case where the government has claimed to have "won" a case it plea-bargained for time-served?