A close friend of the Duke of Cambridge has been banned from the road for a third time after being found guilty of drink-driving in his £90,000 sports car following a visit to one of his exclusive London nightclubs.
Guy Pelly was barred from driving for two and a half years and ordered to pay £7,120 in costs and fines.
London's Westminster Magistrates' Court heard that it was the second time Pelly has been banned for drink-driving.
Guy Pelly arrives at Westminster Magistrates Court, London, where he was accused of drink driving.
In 2001 he had his licence confiscated for two years after he was pulled over for drink-driving while travelling home to "student digs" after partying during freshers' week at agricultural college.
He was breathalysed and found to have a reading "in the 90s" of microgrammes of alcohol in 100 millilitres of breath - nearly three times the legal limit of 35.
Pelly was previously banned from driving for 56 days and fined £750 for speeding in 2012.
Pelly's car was an Audi R8 GT V10 Coupe
District Judge John Zani said: "You have that previous like conviction. I accept that it is now 13 years ago but that was a serious offence.
"I really highlight the period of disqualification for you, then a younger man of good character, and the court then disqualified you for two years.
"Sadly that did not deter you from, years later, when you were stopped in 2013."
Guy Pelly (l) and Prince William (r) together at the rugby
He added: "What you need to bear in mind is that anybody driving a motor vehicle is in possession of a potentially lethal weapon. And when you drive with excess alcohol, or any alcohol, your thought process can be affected."
Pelly was sentenced today after he was pulled over while at the wheel of his Audi R8 GT V10 Coupe in London's Knightsbridge in the early hours of May 28 last year.
The 32-year-old initially refused to give a roadside breath test before being taken to Belgravia police station to give a sample on an intoximeter machine.
The aristocrat, who recently married Holiday Inn heiress Lizzy Wilson at a ceremony attended by Princes William and Harry, was found to have 52 microgrammes of alcohol in 100 millilitres of breath.
During his trial, defence lawyer Philip Lucas called experts who claimed that radiowaves from Pelly's iPhone had interfered with the machine.
Mr Lucas, who has represented a string of celebrities facing driving offences including football pundit Ray Wilkins, said police radios may also have affected the intoximeter, making the reading unsafe.
But today District Judge Zani ruled that he was entirely satisfied that Pelly was guilty of drink-driving and that the intoximeter machine was working.
Pelly, wearing a smart grey suit, white shirt and blue and white polka dot tie, looked relaxed but blushed as he handed his driving licence to the court clerk.
During his trial, Pelly, from Pimlico in central London, claimed he had drunk two large glasses of red wine with dinner hours before he was stopped and arrested.
But the court heard he told police at the time that he had drunk two beers the day he was pulled over.
Pelly said he stopped drinking at around 11pm, climbed into his car and drove to Tonteria, the Sloane Square nightclub he runs, where he spoke to staff and customers before driving off at around 1am.
He was pulled over just before 1.10am by police who claimed he had accelerated quickly in the luxury car.
But Pelly - who smelt of alcohol, according to officers - refused to give a breath test. He told the court he "was anxious because I thought that I had drunk near to the limit".
Professor Hugh Makin, an expert witness for the defence, argued that the police station intoximeter which showed Pelly was over the limit could have been faulty.
He claimed there was an unusual pause of 125 seconds between the machine recording a baseline reading of zero and it being activated and ready to use.
And a software expert told the court that signals from the radios worn by officers in the custody area may have interfered with Pelly's breathalyser reading.
Dr Peter Thrift said radio waves from Pelly's iPhone may have also corrupted the reading.
But Judge Zani said there was no evidence that the machine had malfunctioned and Pelly's claims that he did not drink at his bar on the night in question were not credible.
He said it was "curious" that Pelly described the wine he drank as "house red" - a description usually used in pubs and bars.
The judge added: "Notwithstanding exhaustive expert evidence and lengthy submissions made on his behalf, I am entirely satisfied Mr Pelly has not produced any evidence that raises the realistic possibility that the evidential breath machine in operation at Belgravia police station malfunctioned and produced inaccurate or unreliable readings.
"I am able to state that I am entirely satisfied that Mr Pelly has either deliberately chosen to underplay the amount of alcohol that he consumed in the period of time leading up to his arrest in the early hours of 20 May 2013, or his memory has genuinely failed him."
And he said he was "entirely satisfied the offence with which Mr Pelly stands charged has been amply proved beyond any reasonable doubt and that he is guilty of the offence of driving with excess alcohol".
Melissa Millin, defending, said Pelly's past drink-driving conviction was a "stern and stiff" sentence while he was young and naive.
She said: "It is reminiscent of a time when Mr Pelly was attending agricultural college, it was freshers' week, he was driving with a friend, they were going from a bar back to his student digs.
"It was in the '90s, a very high reading at a time when he was younger and foolish. It was a stern and stiff sentence reflecting the high alcohol in the reading, it was probably to teach men like this a lesson."
Pelly, who ran celebrity nightspots Mahiki and Whisky Mist in the past, has been in the Princes' inner circle for years.
His mother, Lady Carolyn Herbert, was good friends with the late Diana, Princess of Wales, and he organised William's stag party in Devon three years ago.
His grandmother, Monica, was a member of the Tate & Lyle sugar dynasty.
He told the court he would pay his £7,120 in fines and costs immediately by card. This included a £2,000 fine, prosecution costs of £5,000 and a £120 victim surcharge.
He declined to comment as he left the courtroom today.