Sockpuppets are created when an individual creates multiple accounts in an effort to cause confusion, distortion or deception. When sockpuppets are identified, this is a case where the normal policy of Assuming Good Faith is no longer applicable and when warnings or long term bans/blocks are to be considered.
Sockpuppetry can apply for cases where IP or anonymous users are involved but this is after it is determined that the IP user related to a main account is deliberately doing so, as it is possible the editor simply forgot to log in.
Identification of sockpuppetry can vary in terms of difficulty. Some offenders make it easy by referencing a previous account or have the same writing patterns, etc. Other offenders will attempt to differentiate themselves by adopting different writing patterns and treat each account as its own personality, requiring further investigation such as IP lookup. Below are scenarios where sockpuppetry is most common.
An user whose main account is blocked/banned for various reasons but instead of contacting admin in order to negotiate removing the block/ban, they choose to create an alternate account in an attempt to continue the same vein of behavior that first got their account blocked/banned.
The user creates multiple accounts all sharing the same opinion in an attempt to create a false sense of consensus. Essentially, they are posing as multiple people to further their own agenda.
The user might create an alternate account in an attempt to avoid negative repercussions to their main account. In these cases, such people should still be held responsible for their own actions as attempts to avoid having one account per editor is a breaking of the trust required in a wiki where everyone joins in.
In cases of sockpuppetry, the sockpuppet account will be blocked/banned immediately. The length of the block or ban will depend on the circumstance, although it is possible there could be exceptions, such as when an user creates a new account when they do not recall the login for the main account. However, in these cases, the user will likely self-identify right away their need for help with their main account.
The main account that the sockpuppet account is linked to will be blocked/banned too. If it is already blocked/banned, the length of the block will be extended.
Perma-bans will be considered for extreme cases.