The mod team has been keeping a close eye on this post, as it's obviously generated a fair bit of controversy and concern from some of the community. Since it's still gaining new votes and comments, we thought it would be a good idea to just remind the community of what options are available to them if they take issue with any moderator's behaviour.
First off, as always, meta is always available if you wish to discuss or dispute how certain posts were handled. Although it's not really the best place to discuss every action you disagree with, it is a fantastic way for getting the entire community to weigh in, or to go into a post more in depth than you could in the comments.
Flags are another option available to you. Comment flags are of course the go to if you've got an issue with a moderator's comments, and think it breaks one of our commenting rules. It's something that's happened before, and when it happens, another moderator will take a look at the flag. If we action the flag we'll normally make a point to poke the moderator in question to let them know.
If you disagree with how a moderator handled a question or answer, then flagging the post is the best choice. This applies even if you already flagged the post previously, and the flag was declined. In situations like this it's best to use a custom flag, giving a bit of detail on the issue or why you think this post should be given a second look by the mod team. When situations like this occur, a new moderator will be the one to take a look at the new flag (unless, of course, the original mod sees it and goes "oh, huh, oops! My bad!", which I've definitely done before).
Ping Mods in Chat
Another option is chat. Most of the mod team are frequent chat users, so you can always ping a moderator in The Bridge or create a new room an invite a moderator to it if you wanted to discuss something with them. There's ways for moderators to make rooms private as well, should you wish to discuss the issue with a mod privately, all you need to do is ask.
Escalate to Community Managers
If you have have serious issues with a moderators behaviour, then you can escalate the issue to Stack Exchange by using the Contact Us form. Either the "Report/Dispute a Code of Conduct Violation" or "Other" would be the best subject for such a situation. Rest assured the moderator team isn't involved in this process at all, so we'll never see what you submit, or even know you submitted something in the first place.
Use the 10k Moderation Tools
Something else I'd like to draw attention to, as already pointed out by Wrigglenite in the comments, is that users with 10,000 reputation have access to the Moderator Tools privilege. The tools page offers a lot of insight into both community and diamond moderation on posts, such as close votes and deletions.
So that's pretty much it, although if you think we forgot anything, by all means let us know in the comments.