This is a civil case, not criminal, so there is no guilty or innocent. If we are talking about criminal libel, which some states have on the books, then yes, the state would have to prove all of the elements of the crime beyond a reasonable doubt.Just liable or not. And yes, if you don't respond to a civil suit, you're found in default and you lose. When you do respond, you file your answer which is supposed to contain (among other things) all of your affirmative defenses, i.e., stuff which you have to prove as a defendant, which if true, means you win.