How to deal with people creating two or more accounts to game reputation?

Question

There's been one abusive person on SO that I've been watching, whose reputation was somewhere around 20, which suddenly jumped today to 181. The answer to this quickly became clear, however, when you look at this question: https://stackoverflow.com/questions/1419816/problem-in-xmldatasource. He has created an alternate account, which he rated up for answering his own questions, enough that it can now vote for him. It has voted for nearly every one of his answers or questions, bringing a 20 reputation to 181.

Is there anything that can be done to deal with situations like this, where a single user is purposefully gaming the system with two accounts to raise their reputation?

As well, on mechanics--are there any mechanics in place to offer some sort of guard, to prevent a user from continually voting another user up? This might aid in situations like this, or situations where RL relationships devolve into continual point-fishing.

Edit: This specific situation seems to be finished now, with both users no longer existing. Thank you, everyone, for the help.

Answer 1

Report them to a moderator. Moderators can cross-reference IP addresses and see if there is in fact accounts that match. Once that's done it will be up to the moderators and/or the Jeff & Co. to decide. Often times the accounts are merged. There are also chances are the user will be suspended or banned.

There are also other methods to counteract gaming, which includes the ability to see how much someone is voting up and down on another person. This will allow us to find some gaming that goes on.

Answer 2

Quote from: More Voting anomalies in the StackOverflow blog.

1. We can automatically detect sockpuppet accounts now. Sockpuppets used for the purpose of upvoting or downvoting will be deleted, and their votes — cancelled.

2. We now perform a more detailed statistical analysis on voting patterns. Any voting patterns that are too far outside the statistical norm will be nullified.

Answer 3

I did notice what looked like obvious sockpuppetry here and the sockpuppet accounts appear to be deleted so I'd say the detection process works! Only the useless sock puppet posts still exist :/

Answer 4

I do suggest to keep the Q at SO, but to delete the answer that was provided. Even though the Q might never be answered, it's still possible for others to provide good answers, which could be upvoted.

While sockpuppets might just ask Q's to gain reputation, this should not mean that the Q's themselves should be considered invalid. Just "kill" the sockpuppet and provide alternative answers.