Deputy Auditor-General's overview

New Zealand Police: Enforcing drink-driving laws.

Drink-driving and speed are the two leading causes of serious road crashes in New Zealand. This report sets out the findings of a performance audit that focused on alcohol. We wanted to better understand why, between 2001 and 2010, there has not been the same reduction in alcohol-related deaths as there had been in deaths caused by speeding.

After we began our audit, the 2011 road toll was released. It showed a significant decrease in the number of road deaths, from 375 in 2010 to 284 in 2011. The number of alcohol-related road deaths fell significantly, from 142 in 2010 to 85 in 2011. The 2012 road toll was 308, which is the second-lowest annual road toll since 1952.

New Zealand has adopted a "system approach" to reducing the effect of alcohol-impaired driving, where agencies with road safety responsibilities work together to achieve shared road safety outcomes. The agencies carry out a range of activities, such as breath-testing drivers for alcohol, raising awareness of the effect of drink-driving through television campaigns, improving road layout, and eliminating roadside hazards. Our audit focused on the responsibilities of the New Zealand Police (the Police) to enforce drink-driving laws by looking at how effective their breath-testing has been.

When considered together, trends in breath-testing and indicators of reduced alcohol-impaired driving suggest that the Police's enforcement work has had a positive effect. Since the mid-1990s, there has been an overall increase in the amount of breath-testing and a corresponding decrease in alcohol-related road crashes, particularly in the last few years. Surveys during the same period show that fewer people believe that there is little risk of being caught drink-driving. In recent years, the number of offences that the Police detect has reduced.

We found strengths in how the Police enforce drink-driving laws. The Police have a clear national strategy that Police officers understand well. This strategy is based on, and supported by, international research on deterring and detecting drink drivers. Our auditors observed Police officers strictly enforcing drink-driving laws, using consistent processes for testing drivers, and dealing with offenders and treating those apprehended with dignity and respect. Police officers use local knowledge, experience, and professional judgement to react to changing circumstances and priorities.

We could not form a view on whether the Police are as effective as they could be because the available information is inadequate. In part, this is because the Police's breath-testing combines with many other road safety measures to reduce alcohol-impaired driving and improve road safety. Attributing results to the Police's breath-testing enforcement activities alone is difficult.

However, when we observed Police in action, we saw efficient practices (for example, many non-alcohol-related traffic infringements are detected and dealt with at checkpoints). In this report, we comment on some aspects where the Police could be more efficient.

In my view, the Police need to improve how they assess and report on how effectively and efficiently they enforce drink-driving laws. They need to monitor indicators consistently over time to better understand their performance. This will allow the Police to identify where gains can be made to have the best results. The Police need to report on their performance in a way that clearly shows how effective and efficient they are over time.

The Police, together with the New Zealand Transport Agency, are seeking to improve how they assess and report how effectively and efficiently they enforce drink-driving law. We consider that agencies working for safer roads should co-operate better to understand how effectively enforcing drink-driving laws can be combined with other activities to achieve better results.

The Auditor-General, Lyn Provost, was previously a Deputy Commissioner of Police. She has complied with our Office's conflict of interest policy and has not been involved in this work. As the Deputy Auditor-General, with the same powers and functions as the Auditor-General, I have overseen this work.

I thank the Police – particularly the staff at Police National Headquarters and Road Policing Managers and their teams in the Districts my staff visited – for their time and co-operation.

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Phillippa Smith
Deputy Controller and Auditor-General

7 February 2013

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