A jury was ordered to find a defendant not guilty of a charge of attempted grevious bodily harm after a key witness failed to show up at court.

Daniel Jeffries was due to give evidence against 35-year-old Mark Newcombe, of Jerome Way, Shipton-on- Cherwell, but did not appear at Oxford Crown Court yesterday.

Mr Jeffries, 18, was one of four teenagers Newcombe is alleged to have driven his vehicle at after he caught them smashing up his van last June.

The court had previously heard that Newcombe drove after the group on the van's wheel rims after the tyres were slashed.

The dad-of-five denies the remaining charges of two counts of GBH with intent, one of attempted GBH and one of dangerous driving.

Giving evidence yesterday, forensic collision investigator Pc Mark Howard told the court there were marks left at the scene of the incident that suggested a "deliberate and conscious" swerve to the left.

There was no sign, he said, that the driver had attempted to apply emergency braking.

The court heard that in tests Pc Howard had carried out with a colleague in similar circumstances, their vehicle did not veer to the left accidentally.

He added: "The conclusion I drew is that the deflated tyres would not have caused the vehicle to deviate from its path along the road."

He denied Newcombe's defence barrister's claims that the tests were inaccurate because a different vehicle was used.

The case continues.