A police chief has taken himself to court after a force vehicle was caught by a speed camera.
The chief constable is a national spokesman on roads policing
South Yorkshire Police Chief Constable Meredydd Hughes pleaded guilty on behalf of the force to failing to supply the driver's identity.
The force was fined £500 by magistrates in Rotherham on Thursday.
The court heard "diligent inquiries" failed to track down the driver of the car, which was caught travelling at 47mph in a 40mph zone in June.
Mr Hughes, who is head of road policing for the Association of Chief Police Officers, pleaded guilty by letter to failing to give the identity of the driver who was guilty of speeding and did not appear in court.
After the hearing, he said: "There are a comparatively few number of cases each year where we cannot establish the driver of what is often a hire car being used by officers enquiring into murders and other serious incidents.
"In the enthusiasm to follow up these inquiries, it would appear that our own internal rules about log books have not been complied with.
"We are looking at ways of ensuring that those who have the responsibility in every district or department for the correct use of police vehicles will be held accountable in future by the courts."
Last month, a South Yorkshire officer was cleared of speeding on his way to pick up a Chinese takeaway after being caught by a camera on the same road.
Pc Stephen Akrill, 41, was caught by the speed camera driving a police Land Rover at 48mph in a 40mph zone. But he said he was on his way to an accident and magistrates, who heard the officer had ordered the takeaway in advance, cleared him.