What a nasty incident. You did an incredible job!

My suggestions which may or may not have been suggested:

• File a citizen complaint with the police department. Almost all police departments have Internal Affairs or Office of Professional Standards. Some are better than others.
• Request a copy of the SOP's (Standard Operating Procedures) on Officer Courtesy and K-9 Units. The Freedom of Information Act requires them to give this to you at nominal charge
• Ask them how long it will take to adjudicate your complaint. (hmmmm....she's serious)
• Don't threaten anyone and don't expect an apology. Government is very afraid to admit culpability these days. But if you get one, that would be awesome!
• Write a calm, reasoned letter about the importance of courteous behavior by law enforcement in the community. Explain how your encounter rings the bell of importance regarding relationships between the citizenry, the community and the police department.
• Send this letter to the Editor of the local paper. CC the police chief or the acting chief (I just read above), mayor, city council or other local representatives.
• Call the council member who represents you and ask for their help to resolve this matter (you are all about what's right for the community and know that he/she is too, right?)
• Also, ask if officers receive ongoing training in public contact and officer courtesy.

At the very least, if K-9 Standard Operating Procedures doesn't specifically cover feces removal on private or public property, with or without permission...it darn well ought to.

If they ticket you about the cars, see an attorney about "harassment". Remember you are a tax paying citizen and have every right not to be verbally assaulted. It's doing the community a service. I hope they do the right thing and get this into the officer's personnel file. Their may be a reason he handles dogs...less exposure to people...food for thought.

Good luck. Interested to know how this plays out.