Fewer blood tests may be due to cost

In the Wellington policing district, 408 blood samples were analysed in 2011. That number fell to 347 in 2013.

The number of blood samples analysed by police in the region has declined 15 per cent since 2013 - and a Wairarapa barrister says it may be because more drink-drive defendants are satisfied with the accuracy of breath testing results.

In the Wellington policing district, 408 blood samples were analysed in 2011. That number fell to 347 in 2013. Similar declines have occurred across the country, police statistics show.

Carterton barrister Jock Blathwayt said the potential cost of blood testing might be putting people off. "People do elect not to go for blood potentially because it's a greater cost. If you're well over the limit, there's no point."

Mr Blathwayt said it is "normal" for police to ask someone convicted on the analysis of blood to pay for medical costs and administration, and lawyers are usually left out of the decision to choose a blood test.

Mr Blathwayt said defendants have the right to seek blood testing and the law treats defendants as if they have been offered it. "Legislation is premised on the fact that a defendant has the ability to go for blood if he or she thinks there is something wrong with the procedure. Courts now apply the law on the basis that, because a defendant has that protection, police can proceed without applying the law to breath testing. "

National manager of Road Policing Carey Griffiths said those charged would be asked to pay for the cost of medical analysis. But he said the reduction in both blood and breath samples was attributable to wider influences including alcohol licensing restrictions, NZ Transport Agency campaigns and ongoing police testing. "The point of this is to provide deterrents through large testing of many people, creating the perception [of widespread deterrence.]

Lowering the breath alcohol limit to 250mcg from December 1 this year has been another influence.

"We regularly strike people who think the drink drive limit's been lowered already."

Drivers who refuse an evidential breath test must undergo a blood test. Courts will take the results of a blood test over the results of an evidential breath test.

Independent nurses or medical staff usually take the samples as legislation means police cannot take blood tests.

Drivers also have the option of asking for their blood test to be conducted by an independent analyst.

Land Transport statistics show 1600 drivers a year refuse to provide a blood sample. Police estimate an average of 8764 breath tests of drivers are undertaken each day in NZ and 100 people are charged with drink-driving.

- NZME.