A Christchurch businessman has beaten the drink-driving law because he struggles to give blood.
Judge Edward Ryan on Thursday acquitted Bruce Edward O'Malley, an entrepreneur and helicopter pilot, on a charge that he refused to provide a blood sample.
Judge Ryan said police had arrested O'Malley too quickly after hedeclared "once is enough" after a failed attempt to extract blood from his right arm.
Police needed to suggest other options before people were arrested for a refusal to supply blood, he said.
O'Malley failed a breath-test near an alcohol checkpoint in Gloucester Street, central Christchurch on January 27.
It showed he was over the limit but he elected a blood test, which overrules the breath reading as long as the reading is under 600 micrograms of alcohol per litre of breath. O'Malley's was 559.
At the Christchurch Central Police Station, registered nurse Patrice McGregor tried to take a blood sample but O'Malley's physiology means he has great difficulty in providing venous blood.
"I would be the world's worst intravenous junkie," O'Malley said after the hearing today.
In evidence presented in Christchurch District Court, the nurse Ms McGregor said she tried for about 30 to 60 seconds using his right arm, after which O'Malley said he had co-operated but "once was enough".
He was then arrested by Constable Hayden Sincock for refusing to give a blood sample.
O'Malley's counsel Pip Hall told the court the offence obliged the police to show an intention to refuse a blood sample.
His client had co-operated and after he said "once was enough" no attempt was made to persuade him to take other avenues.
Judge Ryan said that although some "might feel cynical" about O'Malley's choice, he was entitled to the same rights as anyone else.