I have a very contrary suggestion to others in this thread. Not that I'm necessarily recommending this, but something to think about.
eltonioni wrote:I received a parking ticket from a private car park operator the other day with my (quite distinctive) registration on another car miles away in Dartford and photos to prove it.
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But they also advised me to report it to the police so I "won't be held liable for other offences committed by the vehicle".
I don't see how you'd be held liable. In fact, quite the opposite. A criminal prosecution needs to be decided "beyond reasonable doubt" and a civil dispute requires the case to weigh against you "on the balance of probabilities". Normally, recording just a numberplate would be enough to swing it. In your case, you have evidence that a mere numberplate is not enough to identify your vehicle. If that's all the evidence there is, then proof that another vehicle exists with the same numberplate is surely reasonable doubt. So that ticket, photos and correspondence from an independent witness you have there? That's your get out of jail free card. As independently recorded evidence, it's way more powerful than your word on a police report. Don't lose it!
The downside of course is that you'd have to go through rigmarole of defending yourself, and there's always a risk that a court will fail to see sense.