All you have to do to get around most charges of slander and libel is to preceed your statement with, "In my opinion.....".

I work for a newspaper. Around here we have a saying, "The truth is an absolute defense against a charge of libel." Only say what you can prove to be true and you are safe against a verdict (but not the suit itself). Of course, we have a law firm on retainer at all times to answer any suits people want to file.