Just my two deci-ISK, but I don't think most megas give a damn what their low-level employees say or do on their off hours. So long as it doesn't impact efficiency, or reflect poorly on the parent corp, the effect of letting them do as they please is negligible. And the cost of attempting to ensure each and every citizen is fully 100% loyal and complying with company policy every minute of every day would be overwhelming. We're talking billions of people per planet, and there are a -lot- of planets in Eve. The fact that the megas can operate like they do at all is awe-inspiring just by itself, nevermind the sort of bureaucracy that would be required for the level of thought-police needed to counteract general free-speech.
Granted, if someone says something that -does- infringe upon efficiency or solidarity, that might be a different story. But 80%-90% of the time, I really can't see the mega worrying too much.
I'll also cast my vote in that the main point of the news flash wasn't necessarily that Caldari have civil rights (which is an efficiency thing; happy workers are productive workers), rules, regulations, whatever you want to call them. Rather, the focus was more on the CPD raid itself. Which, as I understand, was conducted on some pretty shaky legal ground, if indeed it was conducted on any legal basis at all. From the sound of things, the Provists might be getting a little too morally superior for their own good.
I myself, with my Gallente leanings, will be watching with popcorn and great interest.