I'll try walking through this code in more detail to see if I see anything. The one thing that I did see was your Page_Load code (it's possible you removed this before posting) - the call to DisplayCurrentArrest, which loads the user control is only being run if IsPostBack = false. You need to load the control on every hit, not just on the initial load.

>

>protected void Page_Load(object sender, EventArgs e)
>{
>     this.oArrest = (Arrest)RegisterBizObj(new Arrest());
>     // Lots of code removed
>
>     if (!IsPostBack) 
>     {
>           // Verify we have a Case Record
>           if (this.oCase.Entity.HasValues)
>          {
>               this.DisplayCurrentArrest(arrestID);
>          }
>     }
>}