Traffic Ticket Question

FWIW...In this case a dash cam would have provided hard evidence, in that the audio track would pick up the tick-tick-tick of the turn signal. This is a good reason not to turn off the audio recording, which is an option on some dash cams. (I've mounted a Mobius dash cam under my rearview mirror...I chose this brand because it's cheap and unobtrusive; you hardly know it's there.)