I had a "no left turn" ticket for $124 in Calabasas CA eleven years ago. It was just a few moments after I had landed coming from Germany on Visa Waiver (you do not always think of reading the days and times left turn is allowed...). I had paid the ticket at the Calabasas Municipal court and kept the receipt in my passport... until my passport expired.
In the meantime as far as I know Calabasas is part of the Los Angeles County court system, which would make any receipt unavailable if I asked a Los Angeles court. Furthermore, since I had presented my Swiss Driver License to the Police Officer there was obviously no record of the ticket in my Michigan driver's license.
I had not mentioned any ticket because I wrongfully thought that traffic tickets were excluded as for the I-485. I mentioned all tickets including this one at the interview. The IO updated my application and that was it.
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Detroit DO - NSC
09/28/98 Entered on K-1 (Fiance) Visa
12/19/98 Married with US Citizen (still happily married 9 years after )
12/24/98 Filed I-485, I-130, I-765 in OKC (NSC)
01/03/99 Moved to Texas (TSC)
05/xx/00 Moved to Eastern PA (VSC)
11/xx/00 Moved to Central NJ (VSC)
03/19/01 LPR
03/xx/03 Received GC dated 03/19/2001
03/20/07 N-400 Priority Date
04/12/07 FP done
09/19/07 Interview passed
10/26/07 Naturalized Citizen