According to what my uncle the corporate lawyer told me beforehand (roughly speaking), and according to the paper I had to sign detailing my rights and responsibilities, "The original or any true copy of the ticket containing all material information required by 12-2804 of the Philadelphia Code is prima facie evidence that the violation occured, and the issuing officer will ordinarily not be required to be present at the hearing."

I assume Dan's infractions that he contested were more of a moving violation nature? (Knowing Dan, at least...)