A millionaire businessman is facing jail after he was convicted of causing a fatal crash by letting a drink-driver take the wheel of his luxury car.

A jury yesterday decided John Nichols, 58, was partly responsible for the tragedy because he could and should have prevented it.

Nichols allowed fellow company director Mary Butres, 48, to drive them back from a day at the races after they had shared a bottle of wine.

She later lost control of his Jaguar XJ8 when she hit standing water on the A1 at Great Ponton, near Grantham, at more than 110mph in torrential rain.

The Jaguar smashed into the Ford Fiesta of Mark Crompton, 20, and Jodie Brown, 19, which had broken down near the central reservation.

The couple and Miss Brown's brother Nick, who were walking away from the stranded car, were then themselves hit, Lincoln Crown Court heard.

The impact was so powerful that Mark Crompton and Jodie Brown were catapulted all the way on to the opposite carriageway and killed.

Butres, of St Mary's Street, Stamford, admitted two charges of causing death by dangerous driving as a result of the tragedy on May 12, 2007.

But Nichols, the owner of a Cambridgeshire packaging company, denied the same offences, claiming the crash was beyond his control.

Giving evidence, he disputed that he should never have let Butres drive after she had "two or three" glasses of wine at Nottingham Racecourse.

Nichols denied he should have realised her actions were endangering lives, insisting: "I had no idea of what speed we were doing."

After considering its verdicts for almost six hours, the jury convicted Nichols, of Manor Road, Carlby, by a 10-2 majority.

Nichols and Butres were both granted bail by Judge John Milmo QC but are expected to be jailed when they are sentenced next month.

Both were previously sentenced to imprisonment after they were convicted following an earlier trial at Nottingham Crown Court last year.

But a retrial was ordered by the Court of Appeal after their lawyers claimed jurors were overhead discussing the case on a tram.