You will usually be informed of this by receiving a "Notice of Intended Prosecution" which requires you to assist in identifying the driver of the vehicle at the time of the alleged offence.
The penalty for not providing this information is a 6 point licence endorsement and a fine of up to £1000.
If you do not know who was driving the vehicle you need to show that you have exercised "reasonable diligence" to find out who was driving. This would involve requesting a copy of the photograph from the speed camera as a minimum.
If you are facing this situation, contact us now to speak to one of our motoring offences solicitors who will help you with your defence. It may be possible to avoid a penalty if we can show that you have followed all reasonable steps to ascertain the identity of the driver.
If you are the owner of a company vehicle which was identified in an alleged offence the rules are different as records are required to be kept about who was driving the vehicle. Contact us for more information on this.