Steven Barry, of Chatsworth Road, Morecambe, claimed that as the manager of People's Mobility Scooters Ltd, he was exempt from the normal road traffic laws when road testing mobility scooters.

But Lancaster magistrates banned him from driving for 20 months and ordered him to pay £995 – on the basis that road tests did not normally take five hours and include a trip to Ladbrokes and the pub.

Barry, 30, was stopped by police shortly before midnight on July 1 after skipping a red light in a mobility scooter and heading across a major junction with no lights on.

He was breathalysed, found to be more than twice over the legal limit and arrested.

Mr Don Green, prosecuting, told the court: "In interview he admitted drinking a pint of beer and seven Jack Daniels and cokes.

"He said one of the scooters had been serviced and he had to take it for a test run at around 6.30pm. He stopped off at Ladbrokes and then went to the Collegian Social Club. After a win on the horses, he went back to the pub for more drinks, then went to drive the scooter back up to work."

Barry drove through a red light in Brock Street at the scooter's top speed of 8mph. He then weaved up Thurnham Street in an attempt to get back to the company offices on White Cross.

Mr Green added: "I understand his defence is that this vehicle is exempt from road traffic rules in his line of work – this is utter nonsense.

"If you are going to take a carriage for a test run – fine. What is not a test run is taking it round town, going for drinks, placing a bet, going for more drinks and then going back to work.

"Frankly that is a ludicrous argument."

Unrepresented in court, Barry, who denied charges of drink-driving and failing to stop at a red light, said: "Regulations making you exempt from road traffic rules do not give a time frame for how long the test drive will take."

Chair of the bench, Mrs Veronica Jansson banned Barry from driving for 20 months, fined him £525 and ordered him to pay £470 court costs.