A CONVICTED drink driver who forged a medical report to try to fool a court into dropping an excess alcohol charge has been jailed for 15 months.

In what the judge branded "an assault on the justice system", Daniel Leach set out to hoodwink Bradford and Keighley magistrates with the fraudulent document, stating that his positive blood test could not be relied on as evidence.

Leach, 33, of New Close Farm, Thornton, Bradford, pleaded guilty to attempting to pervert the course of public justice.

Prosecutor Chris Moran told Bradford Crown Court yesterday the case was "almost derailed" by the fraud.

Leach, who had seven previous convictions, was jailed for six weeks in 2002 for driving with excess alcohol.

In November, 2012, he was arrested after giving a positive roadside breath test. A further sample of breath and a blood test also proved positive.

Mr Moran said Leach was charged with driving with 86 milligrammes of alcohol in 100 millilitres of blood - the legal limit is 80.

He pleaded not guilty and his case was repeatedly adjourned by magistrates at his request.

Leach then forwarded a forged report from Professor Michael Hannah stating that he had a medical condition that made the alcohol reading unreliable as evidence in court.

Mr Moran said when Leach was rumbled he tried to blame his own defence solicitors, Blackwells, for the forgery.

His case was then proved in his absence at the magistrates court.

Leach's barrister, Yunus Valli, said his client had previously abused drugs and alcohol but he was now "substance free."

He had not committed any offences since 2007 and he had been imprisoned just once, in 2002, for drink driving.

"No doubt it was with that in mind that he forged this document to try to avoid a similar fate," Judge David Hatton QC said.

He told Leach: "You have pleaded guilty to doing acts tending and intended to pervert the course of public justice. Having been charged with an offence of driving over the prescribed limit, you took it upon yourself to be caused to be created a letter from a doctor seeking to suggest that you had a defence to that charge, which you did not. The document was forged."

Judge Hatton said it was a plan to "brazenly interfere" with the course of justice.

"The criminal justice system cannot be assaulted in that way," he added.

Leach, who wore a blue jumper, light blue open neck shirt and jeans, showed no emotion as he was led off to the cells.