Can a parking enforcement person keep you from leaving?

I was returning to my car (in LA) just as the meter was scheduled to run out. As I reached my car, a parking enforcement car zoomed up (truly zoomed) and the guy jumped out. I told him I was just leaving, but he said, "It's too late. The meter's red." He took out his electronic gadget & started issuing a ticket.

I would understand if he had just issued it, or if I arrived at the car in the middle of him issuing it, but he didn't arrive at the car until I reached my door to go. Does he have the right to write me a ticket in that situation--to make me wait when I was completely ready to leave? Any suggestions on fighting this $50(!!!!) parking ticket?

Also, he wrote the wrong color & only 4 digits of the vin# on the ticket and had the nerve to write that the vehicle was "unattended"! Help!