Problem with database query

Hello I now have a new problem.

Here is my code.

PHP Code:

$acceptal = $this->db->select(array('posts.content', 'posts.id', 'posts.userid', 'votes.userid', 'votes.content'))
->join('users', 'posts.userid = users.id')
->join('votes', "votes.questionid = $debate[id]", "votes.content = 'accept'")
->select(array('users.username','users.avatarpath')
)->get_where('posts', array('posts.questionid' => $debate['id'], 'posts.floor' => 0)); 


Here is the SQL it generates.

Code:

SELECT `posts`.`content`, `posts`.`id`, `posts`.`userid`, `votes`.`userid`, `votes`.`content`, `users`.`username`, `users`.`avatarpath`
FROM `posts`
JOIN `users` ON `posts`.`userid` = `users`.`id`
JOIN `votes` ON `votes`.`questionid` = 3 WHERE `posts`.`questionid` = '3' AND `posts`.`floor` =0

If you notice, you'll notice that it is not joined to votes.content = "accept".

How do I do this?

I want to join to another table using 2 criteria, not just 1 criteria (the code is only joining to the table with 1 criteria).