Laws aren't politics, they're the result of politics. Politics is the process, the debate. The end result of that political process is laws.
When we say "no politics" here, we mean to avoid getting into political/ideological arguments... for example, debating whether the Colorado marijuana laws are a good thing or a bad thing. But just mentioning the law itself isn't necessarily a "political" post.
I know, it seems like maybe I'm splitting hairs... but my "cutoff point" for what I consider discussing politics is members getting into political/idealogical debates on a subject. That sort of thing we don't want to get into here.