Who's free to speak?

I've been thinking about Wednesday's class and the topic of who gets to decide who is free to speak. It was interesting analyzing the ads because even though they were wanting the slaves to be "free" they still didn't want black people as equals. I'm sure they didn't want any blacks in power and the idea of a black president wasn't even plausible to them. There just seems to be a lot of hypocrisy during that time. There's a lot of hypocrisy now over the same subject. Who decides what is freedom and who decides who is free to speak? The people in power don't seem very interested in listening to different opinions and different beliefs, so it would be very easy for them (without the critical eye of the public) to stifle unwanted voices. I wouldn't go as far to say that the public is aware of everything that the government does, but we have been trained to look at it objectively.