I was coming off a motorway sliproad in Glasgow and went through a light on orange. I am very sure of this as I saw the traffic police car in my mirror before this occurred and would obviously have stopped if I thought they could charge me. I did not think I would have time to slow down in time. There was no one behind me, they were in the lane next to me, coming through a second or so afterward - they stopped for the light. I was pulled over much to my surprise. The whole way through I insisted it was an orange light. They claimed (2 of them in car) that my car wheels were behind the line when the light went to red. I truly believe this is not true. I am not convinced they would have had a view of my front wheels and the driver of the car would surely have had to be concentrating on stopping their car. They also accused me of accelerating towards the changing light, which is also a complete falsehood. I maintained a constant speed. I am really annoyed at the whole incident and while part of me thinks it would be easy to take the FPN of £60 and 3 points, on a point of principle I am tempted to challenge the charge in court. Does any have any experience of this? What do people think my chances are? I have no previous convictions on my licence. Thank-you.