A good start is to file a formal complaint. This complaint should contain as much detail about what happened, I would also include any FOIA information you could get. Once you mail the formal complaintI would contactthe Chief byphone and/or email about the letter and that you expect a timely response/fix to the issue.
If indeed your rights were violated, then you have grounds for a lawsuit. This is where a digital recorder comes in handy. Some people will see how the formal complaint is handled before following through with the suit. Keep copies of everything you send them for your records, if it happens a second time you have that much more ammo.
EDIT: If you do follow up with a suit, contact a lawyer that is comfortable with 4A cases.