It is entirely true that "tu quoque" is a logical fallacy, it being a specific case of the ad hominem one. The truth or not of something is not dependent upon who says it nor either what they've said ...

On Fox News's imaginatively named The Five program, which airs weekdays at 5 p.m., a five-person panel took on Seattle's kayaktivists this week with the network's trademark wit and intelligence. Hide ...