Check the alleged speed and time of the offence, the police can make mistakes.
If you are summoned for a serious speeding offence caught on camera, you may have a right to appeal if you did not receive notification within 14 days.
If you are caught only a few mph over, ask for a calibration certificate for the machine that caught you. Gatsos must be checked anually.
If you decide to appeal, ask to see police evidence, they are not allowed to produce photocopies or digitally advanced photographs.