I'm all for tilting at windmills if you think it has a point, particularly with respect to elections procedures that you believe to be unconstitutional. So if you think (as the voters do here) that it should be a violation of the Constitution for a state to only allow registered members of a party to vote in that party's primary, then by all means, feel free to make that argument.
But the Supreme Court held back in 1990 that it was unconstitutional for states (like California) to require an open primary when that's not what the party wants. And that decision wasn't even especially close, with only two dissenting votes. (Justices Ginsberg and Stevens, neither of whom, I might add, remain either on the Court or breathing).
Given that the Supreme Court has indisputably said that primaries have to be closed if that's what the party wants, the plaintiff's argument here that it's unconstitutional for a state to allow primaries to be closed is a surefire loser. Even if the plaintiff's request (as here) only that they be allowed to vote for "expressive" purposes and do not ask that their votes be counted. No way that's gonna win; not even back in 1990, and certainly not with the contemporary composition of either the federal or California judiciary.
So tilt away, my San Diego friends; just know that there's a 0% chance of winning this one. The best that you could possibly hope for anyway is to somehow prevail in state court (which ain't gonna happen) and then have that decision summarily reversed by the Supreme Court in a blistering opinion.
But as it is, as expected, you lose -- consistently -- long before that, including but not limited to in today's published opinion by the Court of Appeal.
