Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
If you read the above carefully you will discover that the First Amendment guarantees a RIGHT to free speech, but it does not guarantee a FORUM for free speech. It doesn't say "you can exercise your right to free speech anywhere you want", it simply says that Congress can't restrict the exercise of free speech.
(from Rep Barletta's Twitter feed)
Practically speaking, this means that you can criticize the government all you want. I can call Scranton Mayor Bill Courtright "grossly incompetent" and I can say that Representative Lou Barletta "looks like a Mexican" (that's ironic, get it?) all I want, and that's perfectly okay.
What this doesn't mean is that I have a right to express those opinions using someone else's property, be it physical or intellectual. For example, the Facebook people can very well say that "no postings should be allowed that are critical of Lou Barletta" and that would be perfectly okay. Why? Because they own Facebook and they can make up all the Facebook rules they want. If I don't like that rule, well, I have to realize that there is no (contrary to what you actually read in some dark corners of Facebook) Constitutional right to free speech on Facebook. My recourse is to simply go "old school" and talk to my friends about Lou Barletta or maybe even create my own social media forum where Lou Barletta can be criticized all day and night. Think that's extreme? Well go hunt down former Scranton Mayor Chris Doherty and ask him about www.dohertydeceit.com.