Checkboxes checked but not evaluating to true in the code

The two boxes are checked (cbHidden and cbActive) and yet in the code behind the <checkbox>.checked is false.
Can you help? Thanks.

<asp:CheckBox                     ID="cbHidden" Text="Hidden" runat="server" ClientIDMode="Static" EnableViewState="true"/>
<asp:CheckBox                         ID="cbActive" Text="Active" runat="server" ClientIDMode="Static" EnableViewState="true" />

 
****** in Page_Load under Page.IsPostback = true

           if (cbHidden.Checked)          ...