That's not what you said, so I pointed it out. You stated that you could say
whatever you wanted without legal ramifications. Also, while I don't know if libel and slander would directly lead to incarceration, you can certainly be held legally accountable for them. Plus, like I said, there are always consequences. Go up to a stranger that can kick your a** and tell them off - might not be illegal, but I wouldn't advise it.