> RvW was decided based on constitutional grounds, which means that even if a legislature thought it was wrong, there would be no way to 'clarify' the matter.
That's not true at all, at least rules as written. If the supreme court interprets the constitution and the legislature doesn't like it they have the power to amend it. Thats the explicit check the legislature has on the courts. And yeah it's a huge PITA but we've also done it 27 times.
> In addition to those, there have been many times when the judges have (almost) all been from the same party (the 1930s come to mind); should those cases get deference?
Yes, absolutely. I have no idea why you thought I would say no to this.
Split decisions are fine for first rulings, it's how it goes, people disagree. But when it comes to the courts changing their mind down the road the bar needs to be higher. The previous ruling has been standing for however long without the legislature feeling the need to intervene. Unless there is some new information like a hypothetical ruling that was based on phrenology or an exceptional case where it's clear to everyone that it was a mistake and the logic doesn't actually follow you should give deference.
And look, I know this gives a huge amount of bias to the decision in the first ruling but without it the decisions of the court stop having any meaning. So what if they ruled <thing> is unconstitutional? I can keep doing it because the next time it might not be.
It is pants-on-head stupid that flagrantly violating the constitution on purpose after the law has been settled so you can go back to the supreme court and rule a different way even has a chance of working.
When you have half the court saying the decision as it was originally made was not only not made in error but that it was correct that really needs to be the legislature's problem.