Commons:Checkusers/What's that
What is a checkuser?
Checkusers are highly-trusted administrators with the technical ability to see private data for a user, such as their IP address. This is done to determine whether a user is misusing multiple accounts (multiple undisclosed accounts all controlled by the same editor that are used for fraudulent, deceptive, or otherwise disruptive purposes are normally referred to as sockpuppets).
Checkusers are technically able to:
- Determine from which IPs a user has edited or done a logged action or password reset on the Wikimedia wiki;
- Determine the edits, logged actions and password resets on the Wikimedia wiki of a specific IP (even when logged in);
- Determine whether the user being checked has sent an email using MediaWiki interface to some other user.
The tools are typically used to fight vandalism, to check for sockpuppet abuse, and to limit disruption of the project. Such abuses may have to be dealt with blocks performed by checkusers themselves. The use of the checkuser tools and release of the private data is limited by the Meta CheckUser policy, the WMF Privacy policy and the WMF access to nonpublic data policy. CheckUser actions are logged, but for privacy reasons the logs are only visible to other Checkusers. Because of this, Commons must always have no fewer than two checkusers, for mutual accountability.