ethical dilemma

Everyday on my way to class I pass through a busy-ish four-way stop on campus. This stop sign is right by the dorms and I sit there and shake my head as college students on expensive mountain bikes (that will never see a mile of singletrack) absolutely FLY through the stop sign without so much as a glance at oncoming traffic, let alone something even remotely resembling a stop.

Today on my way home from class, shortly after passing through said stop sign, I look in my rearview mirror to see flashing lights.

I pull over and the cop says in a VERY condescending tone "uh ... there was a stop sign back there" - to which I say "yeah, I know" and he says, "well I was parked behind a bus and I saw you run it - can I have your license and proof of insurance?". Crap.

Here's the thing, I am not 100% sure that I didn't run the stop sign. I mean, I don't particularly remember stopping today, but I KNOW that I habitually stop at the sign. Why would I have ran it TODAY?

I'm considering appealing the ticket for a couple reasons. I'm reasonably certain that I did indeed stop at the stop sign and I'd rather not have to pay the fine (not to mention the potential damage to my driving record!). The fact that this particular cop was pretty much a jerk to me fuels the fire even more. And I have to admit that part of me thinks it would be a little fun to appear in municipal court and argue my case (Is that weird?).

I don't know that I have much to lose.

The thing is - is it unethical to show up and argue that you didn't run the stop sign when you are only 90% sure that you stopped?