The former chair of roads policing at the Association of Chief Police Officers (Acpo) has been banned from driving for speeding at 90mph.
Meredydd Hughes, the chief constable of South Yorkshire, apologised after being caught on camera in a 60mph zone on the A5 at Chirk near Wrexham in May.
He stood down from his role at Acpo after he was summonsed for the offence, which happened when he was on holiday.
He was disqualified for 42 days and fined £350 by Wrexham magistrates.
Hughes, 49, did not appear in person before magistrates but entered his guilty plea via his solicitor, Huw Edwards.
The court heard the chief constable was caught driving at 90mph in his Y-reg Audi at 8.17am on 28 May.
Mr Edwards said Hughes had made a guilty plea "effectively" at the first opportunity, and had fully co-operated with the police.
"With regards to the offence itself, Mr Hughes recalls that on that morning he was returning from north Wales where he was on a short climbing holiday.
"He doesn't seek to make any excuse about this matter. He totally accepts that the police have a duty to do," Mr Edwards said.
"He is no exception and he accepts that he must be punished for the offence.
"He asks me to apologise for the offence. He recognises that the matter is a serious matter."
As Acpo's roads chief, Hughes had argued in favour of "less conspicuous" speed cameras as a way of slowing down traffic.
Cardiff-born Hughes had also served with the South Wales and Greater Manchester forces during his career but returned to South Yorkshire in 2002 as deputy chief constable.
He has been in the chief constable's post since September 2004.
South Yorkshire Police refused to discuss whether a car and police driver would be made available to Mr Hughes during the period of his driving ban.
A spokeswoman said the court case was "a private matter" and referred the inquiry to South Yorkshire Police Authority.
They issued a statement saying: "The matter will now be considered by the South Yorkshire Police Authority in accordance with established procedures relating to this type of incident.
Jools Townsend, of road safety campaigners Brake said Hughes' offence was "shocking" and called the sentence lenient.
"By committing this deadly crime, Hughes undermines the work of traffic police to protect the safety of road users, both within his force and across the country.
"He should seriously consider his position as a result."
But the anti-speed camera group Safe Speed said: "The hypocrisy is breathtaking. Mr Hughes should clearly have been preaching what he practices - because clearly he knows that exceeding the speed limit isn't necessarily dangerous."