I have a Drupal 7 Views that produces a case activities report. It has columns like scheduled activity date, contact id, notes, etc. The user can search by contact id. However, I would like to restrict the case activities that only show up if the user has an existing group relationship to the case records.

I think I'm close. I have the Group ID as a relationship (access control: clients). I just can't get Views to check the login user's CiviCRM group and validate it against the civicrm ACL.

For example: User A belongs to Group A (staff group). In the ACL, Group A can view contacts from Group B (the clients). When the user uses the case activities report, they should only be able to search contacts to which they have the ACL access from in Group B (not Group C, D, etc.). 

The challenge I'm having is filtering the activities on the user login's group ID.