drop down list won't bind properly

I have a drop down list that I populate from a list of users from a stored procedure, and if a users id is in the list of data from the database, I want their id to be initially selected when the page loads.  .  I've tried putting this in page_load, pre_load, etc, but no luck.  When the page first loads, the first item in the list is selected, .  Argh... What am I missing?  

 My code behind to check if their sessionid is in the data from the stored procedure...
Protected Sub Page_Load(ByVal sender As Object, ByVal e As Sy ...