Completely ignore everything you said about how you park there every day. I is completely irelevant. just show up and say you got the ticket at 3:17 and that there was no way you were there for 3 hrs and print the schedule.
Letter is useless in court but you might be able to show it to the prosecutor and say that she is willing to follow up with an affidavit saying the same. But having her show up is best..
That being said... its a pretty cheap ticket...
Bookmarks