Do I need a Police Commander Review Letter from the Police Commander of the District? Welcome to Chicago Police Department's Online Services Portal.File a written request with the Police Board. When you send the affidavit to the companies, attach copies. (NOT originals) of any supporting documents (for example, driver's license or police report). A letter to the Chicago Police Department asking for a copy of your Chicago RAP sheet along with your phone number in case they have questions. The Special Event Permit Application is structured to address many types, sizes, and elements of special events. Please fill in all sections completely. DCASE application package must include the Chicago Police. District Commander's and local Alderman's review letters.