Duke of Westminster's sister tells court she has too many staff and cars to know if she had been speeding

It was an excuse that could only have been offered by one of Britain's wealthiest women.

Lady Tamara van Cutsem, a close friend of the Royal family, attempted to avoid a speeding ticket by pointing the finger at her own household workers, a court heard.

However the 39-year-old noblewoman claimed that she had too many staff members - and too many cars - to remember who was behind the wheel. "I simply don't know if I was the driver at the time," she claimed.

Despite Lady van Cutsem's pleas, magistrates in North Wales convicted her of failing to provide information that could help identify a speeder.

The NZ$1270 fine is unlikely to be a problem, however. Lady van Cutsem is the sister of the current Duke of Westminster, Hugh Richard Louis Grosvenor, who became one of the country's richest men after he inherited their father's $17 billion estate when he died in 2016.

She married wealthy banker and landowner Edward van Cutsem in 2004 at Chester Cathedral, in a ceremony described as the "wedding of the year". The Queen was among the guests, while Princes William and Harry were ushers.

The court heard Lady Tamara's Land Rover Freelander had been captured by speed cameras travelling 35mph in a 30mph zone in Bangor-on-Dee, near Wrexham, on January 15.

Lady Tamara claimed up to ten staff had access to a fleet of six vehicles, including the Land Rover in question. She therefore refused to admit to the offence and suggested that one of her many workers could have been driving over the speed limit instead.

She told magistrates: "We have six fleet vehicles under my name. We have a farm business and it's easier to have cars employees can drive. Whichever car is spare they take.

"I simply don't know if I was the driver at the time. I didn't want to lie on the paper."

The court heard Lady Tamara had told police that the vehicles were used by herself, her husband and ten employees but three of the staff were eliminated after an internal inquiry.

Writing to the speeding ticket department, she added: "It disappoints me the offence has been committed. This section of the road is frequently travelled by this vehicle."

The 39-year-old had already received three points in 2017 for speeding.

Howard Jones, defending, argued Lady Tamara had shown "reasonable diligence" in her efforts to identify the driver. Staff had been quizzed and attempts made to check CCTV and tracking systems.

Jones said: "The defendant receives the notice and then does an internal inquiry to find out who was driving this pool vehicle on that particular date because she didn't believe it was herself and didn't wish to admit to an offence she hadn't committed.

"She didn't want to mislead anyone."

But prosecuting barrister Ember Wong said Lady Tamara, the eldest daughter of the sixth Duke of Westminster, "failed to provide the names of potential drivers", something that was "easily available to her."

Wong insisted that the noblewoman did not do everything she could in the circumstances to reveal the offender to the authorities.

Lady Tamara admitted defeat, and she replied: "Yes, I didn't."

She now also faces $1360 in costs and received six penalty points.

House manager Oliver Harris said procedures had since changed. "We have put in a driver log," he said. "We have had two people speeding post this event but have been able to know who has been driving on both those occasions."

He added: "This was something we haven't dealt with before."