Is it true that 50% of authorities don't chase up on red light offences and what will happen if I say it wasn't me but I can't be sure who it was?
Notice of Intended Prosecution for red light camera offence: if I do not reply is it likely that they will not chase me up with a Section 172. I have heard that up to 50% of authorities do not bother. I was caught in St Albans. Also, if I respond saying it was either me or another named driver driving at the time but I cannot definitively remember we drove various trips that afternoon and using reasonable diligence we cannot say for sure - what happens. Finally, how many times can the NIP notice be passed naming another driver, then again and so on before the authorities get wise and what will they do?
In our experience chasing up red light offences (and indeed any Fixed Penalty Notice) is a process very suitable to computer enforcement and pretty much all authorities will follow with a S172. You are playing Russian Roulette, but with five bullets in the chambers and only one empty so the odds of getting away with it are not very good. If you think about it, it is a little like paying council tax - it keeps churning out the paperwork and if you ignore it eventually the court summons and the bailiffs arrive.
On whether to respond saying you don't know who was driving then the court will again respond with a Section 172. The defence of diligence is very rarely successful and magistrates - under instructions - will no longer accept that there may have been various drivers at the time. By default there is extreme pressure on the registered keeper to name the driver and if they fail to do so the penalties are swingingly high as S172 is intended to be an enforcement clause. If they believe that you are taking them for a walk in your defence they will rack up the fine (£1000 possible).
In terms of passing the NIP on, there are no hard and fast rules on how many times it can be passed on, but each NIP is "tagged" with the date of the offence and at various times reminders will be sent. Beyond 91 days the offence will not qualify to be dealt with as a Fixed Penalty. If the matter of identifying the driver is not resolved before the six months is almost up, in the case of a private owner the NIP will usually trigger a summons against the registered keeper on a Section 172, or against the person the company owner, the lessor or the hire company have identified as the regular user of the vehicle.
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