Should I Fight My Speeding Ticket?

[anteater]

My question involves a speeding ticket from the State of Washington.
About 3 days ago, I got a speeding ticket (my first one in 25 years) on the way to work in Bothell, Snohomish County. I was just coming off a hill and since there was nobody in front of me for 1/2 mile, I tapped on the brakes to slow down a little but didn't ride on them (unfortunately I didn't see the cop). The next thing I knew, there was a motorcycle cop behind me with flashing lights. The officer told me I was doing 47 in a 35 mph zone, but he wrote me up for 40+. He claimed that was what the laser was registering. I assumed it was a radar of some kind. I'm contemplating whether to ask for a mitigation hearing or plead not guilty.

If I ask for mitigation, chances are I'll get a deferment. (What is the procedures for this?) My records have been clean for at least 25 years, 20 of which were in California. Do I need to go to court with my driving records from both CA and WA? Will the court at least have my WA driving records?

If I plead not guilty, will the officer have to show up to court? I wonder if he wrote in his notes that he was actually clocking me at 47. Since he wrote me up for 5 miles over the speed limit, is there any chance the ticket will get dismissed?
I'm not sure what I should do. Any advice will be greatly appreciated.
Thanks!

[Mr. Knowitall]

You were observed at 12 over, and don't seem to be denying that. You were ticketed for 5 over, so the officer already gave you a break. I'm not sure what defense you would raise to the ticket - what did you have in mind?

There are a number of threads here describing mitigation, the exact process for which varies by county. In one thread, a county was described where at the start of the hearing drivers who want mitigation are asked to line up and, once they're done, hearings are held for contested tickets.