Like a lot of people, I've frequently criticized news reports and commentary that draw false equivalence between things that have significant differences in degree or in kind. There's a lot of that going around lately, so it's worth pausing to reflect on why false equivalences can be so pernicious. I do so here without pointing to specific examples, in part because we can all think of plenty, and in part to remain focused on the principles in question: This is not a post about whether X is worse than Y, but about the problems with saying that X and Y are equivalent when they are not.
First, drawing false equivalence is not only "taking sides," it's taking the wrong side. There's a tendency to think that saying "both sides do it" is the way to avoid taking sides in a dispute (and that avoiding taking sides is imperative). But when saying "both sides do it" requires drawing a false equivalence, the speaker is taking sides -- on behalf of the people responsible for the greater sin. A journalist's imperative is telling the truth, not creating the false impression of neutrality by equating unequal things.
Second, drawing false equivalence between unequal sins incentivizes bad behavior. When minor and major infractions draw the same penalty, it should be obvious that some people will realize that they may as well get whatever benefits accompany the commission of major infractions, since they won't be penalized any more than their rival who commits a minor infraction. Say you have two kids, Barry and Larry. Barry steals Larry's pencil. Larry steals 17 of Barry's video games, along with $20 from his piggy bank. You tell them "Both of you took something that doesn't belong to you. You're both grounded for a week." What lesson might Larry and Barry take from that?
That's why people criticize false equivalence in news reports and commentary. Not just because it's lazy and timid journalism -- though it is -- but also because it has negative consequences. It incentivizes bad behavior.