//….but still if you have an injured party it say " you must produce your certificate of insurance if anyone at the scene has reasonable grounds to request it" so more or less on the spot !//
Not so.
//It doesn't say when, or how long until the request must be fulfilled.//
Yes it does.
Instead of guessing, why don’t we have a proper look at the law which danny has very helpfully cited (Section 170, Road Traffic Act, 1988) and digest properly what it says:
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2)The driver of the vehicle must stop and, if required to do so by any person having reasonable grounds for so requiring, give his name and address and also the name and address of the owner and the identification marks of the vehicle.
(3)If for any reason the driver does not give his name and address under subsection (2) above, he must report the accident.
(4)A person who fails to comply with subsection (2) or (3) above is guilty of an offence.
(5)If, in a case where …[an accident where damage or personal injury is caused]…the driver does not at the time of the accident produce such a certificate of insurance or security…
(a)to a constable, or
(b)to some person who, having reasonable grounds for so doing, has required him to produce it,
the driver must report the accident and produce such a certificate or other evidence.
(6)To comply with a duty under this section to report an accident or to produce such a certificate of insurance….the driver—
(a)must do so at a police station or to a constable, and
(b)must do so as soon as is reasonably practicable and, in any case, within twenty-four hours of the occurrence of the accident.
(7)A person who fails to comply with a duty under subsection (5) above is guilty of an offence, but he shall not be convicted by reason only of a failure to produce a certificate or other evidence if, within seven days after the occurrence of the accident, the certificate or other evidence is produced at a police station that was specified by him at the time when the accident was reported.
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You can see that if the driver cannot or does not fulfil his obligation under sub-section (to produce his insurance certificate) he must, as an alternative, report the incident and produce his insurance certificate to the police. You will note that he has seven days to produce the insurance certificate (Sub-section 7) but must report the incident as soon as possible and in any case within 24 hours (Sub-section 6b). He does not have to produce it to a Third Party.
There is therefore no requirement to carry any documentation with you when driving. In summary:
If you are involved in an accident where personal injury or damage to Third Party property is caused you must stop. You must give your name and address and the vehicle identification mark to any person with grounds for wanting it and also give them the name and address of the person who owns the vehicle (if it is not you). If for any reason you do not provide these details you must report the incident within 24 hours and you must produce your insurance certificate within seven days.
Simples !!!! :-)