Refusing service because of political party.

[robvalue]

The "slippery slope" argument is usually bollocks, but I do think it applies here.

I could refuse service to anyone I like, and cite in my defense that I had reason to believe they had [whatever political views]. If pressed, and it turns out they don't, I can just say it was an honest mistake.

You can now, and always could, refuse to serve someone simply because you don't like them. I think you're a jerk, get out of my shop. Perfectly legal. So this changes nothing as far as slippery slopes go.

Sure, in that case I don't think things should be that way. The cake guy can just say he doesn't like the gay couple, telling them to get out. This nullifies the whole idea of protected groups.