A chilling effect is a term in law and communication which describes a situation where speech or conduct is suppressed by fear of penalization at the interests of an individual or group. It may prompt self-censorship and therefore hamper free speech.
One is completely gone. Another hasn't posted in a couple of months (Although I may have accidentally scared him off with a rant). I'd comment on the situation, but I'm afraid of being sued. Even mentioning something in passing might attract unwanted attention, I'd better look into my rights.
I'd give a hat tip to the person who made me aware of this situation, but I'm afraid I'll get him in trouble too.