That's not true... At least it is not consistent with what the vehicle code states. I]
21453. (a) A driver facing a steady circular red signal alone shall stop at a marked limit line, but if none, before entering the crosswalk on the near side of the intersection or, if none, then before entering the intersection, and shall remain stopped until an indication to proceed is shown, except as provided in subdivision (b).
[/I]
So there is a likelyhood that the flash that you saw was caused by your crossing the limit line/entering the crosswalk before making a complete stop.
At any rate, unless and until the citation is received by you, there is not much you can do about it.
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