I have a similar story...
I was 19 years old and on my motorbike going around a bend on, what was back then, a

I had been around that bend very many times before but this one day, while I was banked-over, my front wheel hit something and I came off. I was completely puzzled as to what happened! I wasn’t speeding or trying to get my footrest grinding on the road or anything stupid like that.
Unbeknown to me though, (as I found out later), there was a farm entrance which I had never noticed before because the entrance isn’t very visible, obscured by trees etc., and a tractor had dumped some crud right on the bend in my path. It’s how I imagine you sometimes see a big load bouncing on the back of an overloaded tractor, and a dollop of mud was deposited right in my path.
I ended up in court being prosecuted by the police, even though there were no witnesses, and convicted of driving without due care and attention based on their opinion. I wasn’t speeding but looking back they tried, and succeeded, to assassinate my character based on the fact that I was young and naïve!
At court, I wasn’t wearing a suit and had long hair but most importantly – it was me verses the police and I was trying to defend myself based on the facts as I saw them. (I was never going to win, but I didn't know that of course). I had one previous endorsement for speeding which added weight to their case.
I still own a motorbike and have been down that road many times since, but of course I am older and wiser now. I would be thinking about such a possibility these days but essentially I was punished just for being young and inexperienced. They couldn’t say I was actually speeding, because I wasn’t, and I wasn’t trying to race to prove anything to anyone, I was the only vehicle on that road at the time.
Now maybe it was only right and proper that I was punished for being in the wrong place at the wrong time and so young but to this day I do not see what that achieved other than another 'criminal' brought to 'justice'.
I don’t know if that constitutes the bad character criteria or indeed if that term existed back in 1978, but that’s what happened.