Once a Policy has been published, you have the ability, as an Admin User, to go back and edit the following areas: 

• Policy - Name, Title, Keywords, Policy Author, Set Email Alert, Email Address, List, Alert Date, Alert Subject Line and Policy Image.
• Policy Sections - Title, Description and Choose Section Content of the Policy Sections tab in publish state.  (Able to Add or Remove Sections in publish state.)
• Related Items - Upload Type, Upload Documents, Description, Existing URL, Linked
  URL.  (Able to Add or Remove Related Items.)
• Response Options - Can edit the Text and Properties.  (Able to Add or Remove Response Options.)
• Categories - Can edit which category has been assigned to a policy.
• Email - Can edit the Subject, Email Type and Email Body within the Email Tab.

However, please be aware that this will not alert users of the updated changes.