When sorting by votes, the accepted answer is promoted to the top, regardless of votes - **unless** it's a self-answer, in which case normal vote sort is used without promotion.

See also:

http://blog.stackoverflow.com/2009/01/accept-your-own-answers/
> **No change in sort order.** Normally, accepted answers are “docked” under the question. This is not true for owner accepted answers; they stay in standard sort order like any other answer.

[Accepted Answer not on top](http://meta.stackoverflow.com/a/212197/187228)
> Accepted self-answers aren't pinned to the top.

http://meta.stackoverflow.com/q/93212/187228