Comment by Karrot_Kream

I've posted this on HN before [1]. It turns out that political bias for the mods comes in when comments are on the edge, and their consistent moderation for their political preferences ends up driving out those with opposing political opinions.

[1]: Politically biased moderation drives echo chamber formation on Reddit https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4990476