A few weeks ago, Chloe Sevigny got herself in hot water for calling this season’s episodes of HBO’s series Big Love “awful.” Not surprisingly, Chloe immediately apologized, claimed she was quoted out of context and provoked and tried to make nice with the show’s producers. Of course, Chloe wanted to keep cashing those fat HBO paychecks. But, could HBO really can her for simply stating her opinion? I mean, this is a free country, isn’t it? Of course it is! And also not.

Many agreements in Hollywood contain what are known as “non-disparagement” clauses. These contractual provisions are designed to prevent people involved in films and television shows from creating negative publicity and interfering with the studio’s spin machine. For example, NBC used a broad “non-disparagement” clause to prevent Conan O’Brien from saying what he really thinks about NBC, Jay Leno, or NBC head honcho Jeff Zucker, or subjecting them to a proper dressing-down from Triumph the Insult Comic Dog. (Fun fact for those on Team Coco: type “Jeff Zucker is a” into a Google search box and see what Google’s autocorrect suggests!)

But, what about the First Amendment? Don’t Conan and Chloe have a constitutional right to way whatever they want (and don’t we all have a right to hear Conan riffing about NBC screwing him)? Yes, unless they voluntarily gave up that right in exchange for cash (in Conan’s case, a reported $32.5 million for him and an extra $12.5 million for his Tonight Show staff).

Generally, the First Amendment does not prevent people from privately agreeing to censor their own speech. The First Amendment is only protects people against government action restricting speech. Where a movie studio is imposing the restriction — in exchange for cash — the First Amendment simply doesn’t apply. So, the question becomes simply, how much money will it take to buy silence?

However, California’s Constitution, like that of many states, has a broader free speech right that is not limited to governmental restrictions on the right to speak. So, a non-disparagement clause that does not violate the First Amendment still may violate a California citizen’s right to free speech.

If that’s true, how do movie and television studios (most of which operate in California), get away with non-disparagement clauses? Well, the simple answer is that people generally don’t want to bite the hand that feeds them. Sevigny, for example, knows that her gig on Big Lovewon’t last forever and she probably doesn’t want to give HBO (or its parent, Warner Bros.) a reason to blacklist her from future HBO or WB productions. I mean really, wouldn’t most people take a few million dollars in exchange for only saying nice things about their boss? Especially when they’ve got as smart, accomplished, nice, charming, and dashing a boss as I do! (Please make all checks payable to Ricardo Cestero, Boss.)

Also, as a legal matter, it’s not so clear that actors or actresses could successfully fight these non-disparagement clauses. California courts have been inconsistent in deciding whether these types of provisions are valid. Although courts generally require that any contractual limitation on the right to free speech be clear, unambiguous and narrowly-tailored, some judges have concluded that if someone gets paid to give up their right to free speech, that’s perfectly valid and enforceable, regardless of the clarity or scope of the provision. In short, even if Chloe or Conan wanted to take the risk of attacking a studio like NBC or HBO, they are by no means guaranteed a win, and may burn those bridges for nothing.

So the bottom line is, as much as we might like to hear what actors, actresses and comedians really think about the studios for whom they work, studios will continue to use non-disparagement clauses to shut them up. Or, to paraphrase Fran Drescher in Spinal Tap: “Money talks and [free speech] walks.”