I don't have any concrete examples, so this answer likely won't satisfy you.
Also, I must mention that dang has been significantly more fair the past year or so. It's been a long while since I've really noticed any of the issues I'm about to list.
From least to most concerning:
1. A couple of years ago, dang would regularly wade into gender arguments. And he'd apologize publicly and profusely to women who had unspecific complaints about Hacker News making them feel "unsafe", assuring those women that he felt their pain and would fix the problem.
2. Rules about tone were enforced unevenly. (Again, to be clear, they're now enforced far more fairly.)
Cruel, over-the-top, mean-spirited, Shanley-style [1] derogatory posts from feminist activists would routinely be allowed to stand. People would respond asking why this tone was being allowed on HN, and others would respond with "it's oppressive to tone-police women in tech". Despite all the attention drawn to these posts, they would not be moderated.
At the same time, the slightest acerbic replies against feminist activism were either "deaded" or publicly admonished by dang.
3. This last point is the most difficult to prove, but regular lurkers will know exactly what I'm talking about. Flags were enforced unevenly—they were used as an excuse to minimize community exposure to posts that disagreed with dang's politics.
When a controversial submission that ran counter to the feminist narrative quickly disappeared off the front page despite hundreds of comments, people would complain in the thread (because where else would they complain?). He'd respond, "Hey, this submission received a lot of flags. This wasn't my decision. I'm not closing this thread, so you can continue discussion. But I'm listening to the community by taking it off the front page."
However, controversial submissions that promoted the feminist narrative would often stay up for hours. Those posts undoubtably received tons of flags, too. When people would complain, dang would explain that he would disregard flags for controversial posts if they generated important conversations.
[1]: http://www.breitbart.com/london/2014/12/10/the-madness-of-qu...
