The only automatic system against bad reviewing is the review auditsreview audits. Failing to pass a number of audits will result in an automatic short time suspension from reviewing.
Other than that, moderators recently got access to reviewing statistics for all queues and the ability to manually suspend users from reviewing:
Moderator newsletter, March 2013
Review Queue – Advanced Statistics
We have made a more in-depth set of review statistics available to moderators. Each queue now includes the number of times a reviewer has picked each available action, and what percent of their total actions it represents. This should provide you with a much better overview of how your community is using review, as well as a way to detect those who seem to be reviewing in bad faith and may need to be temporarily blocked (see below).
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Suspending Users from Reviewing
We have implemented a system for blocking users from using the review queues for 1 to 30 days.
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This page also includes a list of user who are currently banned, either by a moderator or due to failing audits. This functionality is available regardless of whether your site has audits enabled.
Moderator newsletter, April 2013
New Audit Stats Available with Advanced Review Stats
We have added some new statistics for your studying pleasure to the Review Audit Stats we introduced in last month’s issue.
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The following new statistics are available on this page in each queue:
- AvgDuration(s) notes the average time that the user spends on each task in that queue in seconds;
- AuditTotal notes the total number of audit tasks that the user has run into in that particular queue;
- AuditPass% notes what percentage of audit tasks that the user has successfully completed compared to all tasks run into within that particular queue.
On the smaller sites, these tools haven't been around long enough for meaningful stats to accumulate. On the original trilogy, however, I imagine the moderators already have a very good idea of who is repeatedly abusing the review system and I wouldn't be surprised if a few review suspensions have already been triggered.