IANAL, but as I understand it, the typical qualifiers for being a protected class tend to be immutable (sex, race, age, disability, color, creed, national origin, religion, or genetic information, per Wikipedia[0].) Obviously you can change your sex and religion, though, and disability status in some cases, though.

Maybe a case could be made for political affiliation under "creed," since there appears to be no specific legal definition for that[1], although the consensus seems to be centered around religious belief.

In any case, since one can (and many people do) change their political affiliations often, I would expect such a law to meet with some extreme legal challenges at the very least, because it seems like such an obvious attempt to game the system, particularly since "discrimination against a political group" is pretty much the purpose of other political groups.

[0]https://en.wikipedia.org/wiki/Protected_group

[1]https://law.stackexchange.com/questions/8686/what-is-a-creed...

People can and do change their religion. I am proof of that.

True. I have to admit I'm having a hard time coming up with rationales that include religion and whatever "creed" is that would exclude political affiliation as well.

I personally think there's something fundamentally undemocratic about barring discrimination against political ideology because that comes too close to interfering with freedom of speech or freedom of association or the exercise of politics itself.