here role id refers to your database value for particular user..so 0="admin",1="owner"..hide in user control where u have done in your master page to displaylistview..
if (Session["USER_NAME"] == null)
{
Response.Redirect("../login.aspx");
}
else if ((Session["ROLE_ID"].ToString() != "0")&&(Session["ROLE_ID"].ToString() != "1"))
{
string errormsg = "You are not Authorized";
string url = "../login.aspx?errmsg=" + errormsg;
Response.Redirect(url);
}
update me if error occurs..