Just as a note, the PMC account is a very specific staff account that is sort of like community relations - they shouldn't really be messaged for support stuff because it can easily get lost in their messages (because they just forward those things to us, they don't directly handle them in most cases). Directly messaging a site/super/admin or using tickets is a better way of getting us to see issues that aren't community-related. The FAQs direct you to tickets or to use the email form in extreme cases (the emails go to Cyprezz).
We do take every report seriously, but with the mod abuse thing it's hard for us to view it that way because we work with these people every day. All of us see all of the other moderators' actions (we have a single hub feed that basically shows us all what all the other moderators are doing, ban messages, ticket replies, etc; it's all visible to all moderators at once), it'd be extremely difficult for a moderator to 'fly under the radar' so to speak and go after people. This actually was something that has happened in the past (like 10+ years ago), we've learned from what happened and applied measures to ensure everybody is aware of what everybody else is doing.
Transparency is important, and we've been making efforts to close the gap of differences between what mods do and what users can see, but for a lot of ethical and user privacy reasons there'll never be complete transparency. When it comes to individual user actions, we've always taken the approach of not specifically commenting on user actions and not getting involved in public disputes. A side effect of this is that it allows the users to effectively control the narrative surrounding mod actions because we don't comment on those & delete discussions about them. There's only been maybe two cases where we've actually made a public post about something that has happened moderation-wise.
We also recently added an exception to member reports when they're filed against a moderator - that moderator will not see the report, ensuring that it can't be silently dismissed even if they tried to.
There's also a larger moderator/report update coming likely this week that will allow users to view their own moderation history, and a few other tools for users to help streamline communication between the mod team and users.
EDIT: I saw your other questions above this too, I'll answer these directly:
If they really are just another member, why is there judgement for the rules more important than anyone else's?
Their judgment isn't necessarily more important - the trust we place in them is the ability to act on them. The trust comes from us seeing what they've done with reports, seeing how they interact with members and believing that they'd be a good member of the team. Sometimes that doesn't work out, but it is what it is - some moderators were only with us for a short period of time, whether it be because they decided they didn't want the role or because we felt they didn't work well with the team. It's rare, though.
The users have a similar control of judgment over what they feel is appropriate or inappropriate for the site. They can report anything they feel like reporting for any reason, and there have been many times where a report causes internal discussion about the content matter and even changes our view on whether we would have deemed it appropriate before seeing the report.
Are they trained to be good at what they do?
Yes. The mod tools often aren't self-explanatory (which is another thing we're still working on), and like 90% of the job isn't really fiddling with tools but rather interpreting the rules and applying them to reports. In the past, we used a sort of buddy system to pair a new moderator with a more senior moderator to mentor them on the tools and directly answer questions. Our team is a lot smaller now than it was back then, so we can't really do this any more, but this was also before Discord was a thing and we had to communicate entirely within a single Skype group chat. With Discord now, we have a multi-channel mod server and it's a lot easier to have different discussions at the same time. New moderators are encouraged to ask senior moderators on stuff, and we strongly encourage them to do so if they have any doubts since it's like the only good way to build a confidence in the role.
What's stopping them from abusing their power?
Other moderators - I mostly answered this up top, but moderators don't work within a self-bubble.
The entire point of moderators is to be a judge of how the rules are being kept, so why would their judgement ever be wrong enough to have to be held accountable?
A lot of rules are explicitly vague or open-ended because we can't possibly list everything that is either disallowed or allowed. Everybody is different and has different thoughts about what is or isn't appropriate as a public discussion, for instance - so the question is more about "how does everybody agree on whether something is allowed or not". Sometimes we don't all agree, and in that case what happens is the moderator errs on the side of leaving it and posting about it on our Discord, asking for what we've done with somesuch in the past or asking for a concrete answer. If the discussion feels like it's going nowhere - which does happen sometimes - myself and Cyprezz will make the final call.
For judgment being wrong to be held accountable, this does actually happen more often than one would think. Generally what happens is another moderator will ping them on our Discord and ask them about a specific case (ie, "@Paril about <link to content / ticket>, can you give me more info about this?"), and the moderator will follow up with them there. Sometimes a moderator is wrong, and they'll be informed about the correct approach & they'll fix it. We generally ask the moderator that made the mistake to correct it themselves rather than having other moderators directly undo or change something another moderator made, since it can get messy if it looks to the user like we're fighting over a decision even though internally it doesn't work that way.
