"Do you know how fast you were going sir"
"Yes thank you"
"Do you mind telling me how fast you were going"
"Yes"
He has admitted speeding. Therefore has confessed to the crime assuming he was under caution.
If he wasn't under caution then the plod may have a job pressing it as the car is described incorrectly and you could claim he was pointing the gun at something else, balance of probability and all that guff.
He was speeding, fair cop guv. Pay up and stop moaning.
We all take the chance and sometimes we get caught
