The prosecutor then appealed that decision to the U.S. Supreme Court, and the USSC reversed the appellate court and remanded the case back to them to determine if the weapon bore a reasonable relationship to a militia.
The U.S. Supreme Court was saying, in effect, that the appellate court cannot say the NFA violated the second amendment unless they somehow determine that the weapon was a militia-type weapon.
This may have surprised the appellate court. They may have thought ALL weapons were protected by the second amendment, so they never even bothered to determine whether Miller's weapon was suitable for a militia.
Anyways, by this time Miller was dead and his partner pled guilty. That was the end of it.
Shows how much you know about the case. The original court did not even try Miller and Layton. Instead, on petition of their lawyer, dismissed the case on grounds that the law in question violated the second amendment, and thus constituted no law at all. The government appealed directly to the Supreme Court, there was no action at the Court of Appeals level. You could know that much just by reading the Supreme Court decision which states:
District Court held that section eleven of the Act violates the Second Amendment. It accordingly sustained the demurrer and quashed the indictment.
The cause is here by direct appeal.
Better do your homework before posting such "made up out of whole cloth" musings.