On politics.SE it happens annoyingly enough that someone asks a question which seems ok (i.e neutral and objective enough), but then they accept a hugely downvoted answer, e.g -20 relative score. That gives such an answer undue prominence. Yes, it's pretty obvious to a minimally-informed user that the accepted answer is (very) contested... but still I think it's an abuse that could be easily curtailed. Namely:
- Make answers with a big enough negative score unacceptable, i.e. remove the checkbox from them, automatically. I'm not sure what the best threshold would be, but I guess -3 (upvote-downvote difference) is a reasonable cutpoint.
Yes, there are some alternatives to this, namely deleting answers, but there's little agreement on politics.SE to delete bad answers that aren't outright abusive. Given the more subjective nature of the topics, you can probably guess why. (There have been some delete/undelete wars [cycles], complaints on meta etc. Some have featured exactly this kind of very-negatively-scored accepted-answers.)