If you are flashed by a speed camera, the registered keeper of the vehicle should receive a Notice of Intended Prosecution (NIP) within 14 days. If you hear nothing within this time, you should be ok. It is possible that the camera had no film in it, or that the image was insufficiently clear to identify the registration mark of the car. Anecdotal evidence suggests that some Gatso's with no film in are set at speeds at or below the speed limit.
The courts usually allow a day or so extra beyond the 14 days to allow for postage. However if it is not posted within 14 days you should be in the clear. If you receive it after this time scale, you should have a valid defence...
If you do receive an NIP, Section 172 of the Road Traffic Act states you must return the NIP Information form with details of who was driving within 28 days. See Defences, if you do not know who was driving. However be aware that you can be liable to a 6 point fine if you do not return the form or provide the information.
If you are not the registered keeper then the police are allowed more time to establish who is the driver. This can often happen, for instance if you are driving a company or hire car or works van or if the vehicle has recently been sold and not yet registered with DVLC.
If you are stopped by a police officer, or there is a police officer at the scene of an accident, the police officer may give you a verbal NIP, and if so a written one is not required.
If there is a significant mistake on the NIP, then you may have a valid defence. However, under the slip rules, the court can make minor amendments and so you will have no defence in such circumstances.
If you have only recently acquired the vehicle, the police may send the NIP to the previous registered keeper, who will then of course inform them that the vehicle has been sold. If this error is your fault (eg for not sending in the registration document with your details) then again this will be no defence. See Speeding Defences.
The police have 6 months to issue proceedings, which may be by way of fixed penalty notice or summons.
