The HoS Drink Driving Campaign

I received this message on Facebook:

This weekend the Herald on Sunday are launching a major campaign to persuade the Government to lower the drink driving limit from 0.08mg to 0.05mg (of alcohol per 100 ml of blood), the same as Australia, Japan and most of Europe.

Drink driving has devastated the lives of many Kiwis at the hands of drink drivers and they are looking for Kiwis to sign up to a pledge of “two drinks max”.

The aim is to gather thousands of signatures to add weight to their message to Government that the blood/alcohol limit needs to be lowered before more lives are wrecked.

The Herald on Sunday have asked to interview people who are passionate about the cause. If you are interested, please drop me a note via Facebook with your contact details that I may pass onto reporter xxxxxx xxxxxxxx or contact her directly as follows:

I was somewhat amused to also get a call from an HoS staffer today asking if I would join the list of prominent NZers who are endorsing their campaign. I remarked that they must not have read my blog posts on the issue, because in fact I have been somewhat vocal about the lack of evidence for there to be a change.

I am not adamantly against a change. If the research stacks up, then a change from 0.08 to 0.05 might well be justifiable. But we are lacking even the most basic data. The Government has said it is changing the law so this data can be collected, and that is a good thing – then a decision can be made on evidence, not emotion.

The two pieces of data I want are:

1. How many deaths and injuries are caused by drivers who currently legally drive with a BAC between 0.05 and 0.08
2. How many people drive with a BAC between 0.05 and 0.08

With that data we can work out the costs and benefits of a law change – how many NZers currently drive safely at 0.05 to 0.08 and how many cause accidents at that level.

The only data we have at the moment is the stats on blood alcohol level amongst deceased drivers. They show over the last five years that 18 deceased drivers had a BAC between 0.05 and 0.08.

But that number is misleading as it includes those aged under 20, for whom it is already illegal to drive with a BAC over 0.03. That knocks it down to 12. That is 12 out of 1,168 deceased drivers or 1% of the total.

Now a lot of research has shown that it is drivers below the age of 25 who cause the most crashes. We used to have different testing requirements for below and over 25 year olds. I would be pretty comfortable with having the current limits for under 20s extend to under 25s.

So I then ask how many drivers aged over 25 were killed with a BAC of 0.05 to 0.08? Just seven? Around 1.4 drivers a year.

Now if we get better data, then I could be persuaded of the desirability of change.  What we need is for blood alcohol samples to be collected from all drivers involved in a fatal accident, and also record how many others died in those crashes. Ideally we would also differentiate those cases where a driver may be over 0.05 but is not at fault – ie they get rammed side on by another driver.

We should constantly look at ways to reduce the road toll, but they should be based on good research which includes looking at what inconvenience or damage is done to current law abiding drivers. Unless you take a balanced approach, then you end up with an end point where say no car is physically able to go at over 30 km/hr. This would reduce the road toll by around 95% – but would greatly reduce the benefits most NZers get from motor vehicles.