The Marquess of Blandford, the disgraced heir to Blenheim Palace, today admitted to launching a furious road rage attack last year.

The aristocrat has more than 20 convictions for theft, drugs and motoring offences. His latest brush with the courts comes after he attacked a fellow motorist, almost crashed into a police car that was trying to catch him and was caught on CCTV aggressively tailgating drivers - all in separate incidents.

Charles James Spencer-Churchill, 51, admitted charges of dangerous driving, careless driving and one count of criminal damage at Oxford Crown Court. The Marquess was also found guilty of a number of related charges during a trial in Coventry last month, which could not be reported until now.

Graeme Kennedy, 39, a motor trader originally from the Isle of Bute in Scotland, was one of the drivers who encountered the aristocrat’s erratic driving in Oxfordshire last year.

Spencer-Churchill cut sharply in front of Mr Kennedy, forcing him to stop suddenly on the A4095. The Marquess then stopped in the road, blocking both lanes of traffic, and ran to the car shouting abuse and kicking the driver’s door.

“He was obviously driving dangerously. He was in a tearing rush and driving very dangerously,” said Mr Kennedy outside court. “As far as I was concerned it was road rage. He was just ranting, it was not very nice.”

Asked what was going through his mind at the time, Mr Kennedy said: “It was very nearly a Range Rover.”

In a separate incident, Pc Keith Dyson saw the two and a half ton 4x4 weaving at high speed through motorway traffic, the vehicle veered dangerously in and out of lanes undertaking other motorists. When the officer tried to apprehend the Marquess, he sped off and at one point almost ploughed into the back of a Vauxhall Corsa.

The police car was recorded travelling at 84mph in a 60mph area and 72mph in a 50 mph zone as it tried to keep pace with the speeding noble. Spencer-Churchill was eventually pulled over near Birmingham Airport in the midst of the morning rush hour on June 16, 2006.

Spencer-Churchill was bailed to an address in South London, from where he can continue to attend the Priory Hospital, which specialises in drug addiction. He will be sentenced for all of the motoring offences in September.

The Marquess is the eldest son of the Duke of Marlborough, who owns Blenheim Palace in Oxfordshire. He grew up on the estate with his sister after his parents were divorced. During the school-holidays, Spencer-Churchill would help sell ice-creams and guidebooks to the 40,000 people who visit the palace every day at the height of the tourist season.

As an adult, the aristocrat was convicted for a string of theft and driving offences, most of which he blamed on his cocaine addiction.

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