Not quite right. Miller and Layton weren't plaintiffs; they were defendants accused of "firearm" possession. Their indictment was quashed in a lower court; although the government tried to reinstate the indictment in courts up the line, Miller and Layton were under no obligation to appear in such hearings, nor were they entitled to any free representation, because they weren't under indictment.
When the government won its case at the Supreme Court, the only thing it won was the right to present a case in a lower court that short-barreled shotguns had no military usefulness; Miller/Layton would then be free to present a counter-argument that the weapons were militarily useful (and had even been issued to U.S. troops in wartime). Since the Supreme Court held that the issue of military usefulness was relevant to the case, the trial judge or jury would have been instructed that a finding of military usefulness would be grounds for acquittal.
Although Miller was dead when U.S. v. Miller was decided, Jack Layton was still very much alive. For some strange reason, though (gee, wonder why) the government decided to offer him a plea-bargain for time served. Given that GCA'68 hadn't passed yet, he had no reason not to accept the plea bargain, which for all practical purposes simply meant the government dropped its case.
Can anyone identify any other case where the government "won" at the Supreme Court and responded by offering a plea-bargain for time served? Some victory.
Not quite right. Miller and Layton weren't plaintiffs; they were defendants...
Oops, I meant defendant. Oh well, I am not a lawyer, nor do I play one on TV.