He had insisted that the phobia, which at times had forced him to hide under seats, was why he refused to give a blood sample to police.
Mr Dempster, 56, told Knightsbridge Crown Court yesterday that he had even worked in a hospital as a porter in his teens in an attempt to cure himself. "But it only got rid of my fear of dead bodies. My fear of needles of blood was heightened," he said.
The court heard that the society diarist, who chronicles the lives of the rich and famous, was initially stopped for speeding in west London last October. Police officers had said that Mr Dempster, who admitted drinking two tumblers of orange juice earlier that day without realising it had been laced with vodka, smelt of alcohol.
A test showed 45 micrograms of alcohol in 100 millilitres of breath - which is 11/2 times the legal limit. He was then asked to provide a specimen of blood but refused, citing his fear of blood and needles.
A doctor who examined Mr Dempster and questioned him decided he had not been telling the truth and therefore had no clinical grounds for declining the police request.
Magistrates, who later convicted him for drink-driving, refused to accept his explanation. They banned him from driving for a year, fined him pounds 250 and ordered him to pay pounds 350 costs.
Counsel argued that the conviction went against "the weight of the evidence".
Judge Timothy Pontius said that considering what Mr Dempster had told Dr Grant Winstock, the police medical examiner had been "seriously wrong" in reaching his conclusion.
"Much court time and public expense" could be saved if police accepted urine samples more readily, he said.Reuse content