It's more complex than discussed above.
First problem, you need a FEDERAL gun crime bust to take to the Supremes, not a state law bust. Why? Because the 2nd Amendment hasn't been recognized (YET!) as being "incorporated" under the 14th, meaning under current theory, even if Emerson goes all the way and the Supremes recognise an individual right, we'll then need to take a state bust up into the Federal system. (Note: Emerson winning with the Supremes WILL most likely help in those states with a state RKBA constitutional clause...which is most of 'em.)
So what's been stopping a push against Fed gun laws the way Emerson is doing now?
1) Emerson could not have happened in the largest circuit, the 9th. The 9th already ruled in favor of the "collective right" argument, so a good judge like the one Mr. Emerson ran into in TX would have been blocked from making that sort of decision. Emerson had to happen in a circuit that hadn't ruled on the 2nd yet - the 5th circuit qualified.
2) There just aren't that many "pure Federal gun law violation busts" made in any given year.
3) Many if not most Fed gun law busts are machine-gun related. The sheer terror of full-rock-and-roll would make any such attempt highly difficult if not impossible. Take Bob Stewart, the guy in AZ the ATF just wrongfully popped over his kits. Years ago in Utah he was apparantly convicted on a full-auto felony bust. As I recall, Utah isn't in the 9th and if so, Bob had the balls and the lack of other criminal intent and records to have made a real good test case to appeal that conviction. But to do so, he would have been risking 10x as much jail if he lost...that's one hell of a risk, and since an MG is involved, the potential jail after not pleading and fighting to the max is pretty extreme, 10 years as I recall. Bob's got guts, but he caved (IF the reports we're getting are accurate). I'm not willing to say I would have done different.
And we wouldn't want to use a sawed-off shotgun case for similar reasons: high jail time if you lose plus Miller specifically clouds the issue.
In conclusion: look how rare the Emerson situation really is. It's a Fed gun bust, that involved a relatively modest gun without totally crazy jail time possibilities, in the right circuit, plus it's clearly a militia weapon!
*And* we got what turned out to be the very best initial trial judge in the nation.
Stop asking why an Emerson type of case hasn't popped up before, and thank God almighty we've got this one!
Last thing: best guess is, the current Supremes will rule in our favor if the 5th agrees with the TX judge. Let Gore get even one nominee before Emerson hits, and it's goodbye Charlie.
VOTE BUSH!
Jim