Will breathalysers change motorists behaviour?

There is no doubt that driving whilst drunk is dangerous. The misery and pain it causes to the families affected by drunk drivers is beyond comprehension. In France, it is a huge problem. Around 4,000 people are killed on French roads every year, with drink driving being the main factor in accidents. Speeding is a paltry second.

The introduction of the compulsory breathalyser will also affect us Brits driving to France. All drivers - French and Foreign are included in the new rule, however there is a grace period until November so we can 'get prepared'. As well as carrying a breathalyser, motorists are also expected to have with them a high-visibility safety vest and a warning triangle.

So will this kit change behaviour? The thought process behind this is quite simple. The French government hopes that with breathalysers in every car, drivers who suspect they may be over the limit can test themselves and if necessary refrain from taking the wheel. They hope it will save around 500 lives every year.

But having them in the car is one thing - getting people to use them is another. It might certainly be the case that having them in the car would 'prompt' a driver to use it after drinking and maybe reconsider the need the drive. Deliberately placing certain objects in an environment can alter behaviour and act as a 'situational cue' like placing running shoes by the front door can prime someone to go running when they get home or think more about a healthy lifestyle.

But it really depends on the driver. Are the majority of 'drunk drivers' really drunk or a little drunk? We know that this doesn't matter because the consequences can still be the same but in terms of understanding behaviour there is a huge difference. If the majority of drivers are a 'little' over the limit they might believe it is ok to drive home. They have just had one glass of wine over lunch and think this is fine - in which case these tests may help them to reconsider. If the majority of drivers are heavily over the limit then it is likely that they would be aware of their drunken state and unlikely to consider the law when they get into their car. No test or triangle is going to prevent them from getting behind the wheel in this scenario. If they know they are drunk - why would they breathalyze themselves? In this case there is no substitute for road traffic policing and the capture of individual drivers who put lives at risk.

Putting on our 'behavioural psychology hat' we think car manufacturers could play an important role in the war on drink drivers. Defaults are the options that are pre-selected if an individual does not make an active choice - in this car choosing not to drive drunk. If cars could be designed to NOT start if the driver fails a breathalyser test the problem of drink drivers would be solved. For us, this would be social change on an industrial scale.

The penalty for not carrying one of these tests is a snip at 11 Euros - less than the cost of buying two tests so there is the possibility that some would 'chance' a fine rather than buy one. In our view this fine is set too low. When mobile phones were first banned at the wheel with a £10 fine for those caught behaviour didn't really change. Add penalty points and a higher fine and flaulting it is more costly to the driver. However, the fear of any fine is enough for some and it might create a strong incentive to purchase the kits. This is likely to be 'law abiding citizens' who arguably wouldn't drive home drunk in the first place.

The French cannot be mocked for this idea. On the face of it this law is a good one and it may lead to fewer deaths on the roads, which surely is a good thing. Even if one life is saved from this idea it will be worth it. But what the evidence suggests to me is that culture plays a strong part in this problem. With so many deaths on the roads caused by alcohol, a cultural change is required in France. It must be accepted that their beautiful Cabernet Sauvignon does not go with motor oil and the turn of a car ignition. It has taken many years of campaigning by both well-funded organisations and victims of drunk drivers to shape the social and cultural norms around drinking and driving. Albeit from a few mindless individuals, behavioural expectations, or rules, in our society firmly place drinking and driving in the 'wrong' category and as a result convictions for drinking and driving in the UK has reduced considerably over the last decade and deaths have also reduced. As a society we have accepted that drinking and driving is not the 'done thing' anymore.

Only time will tell who the real winners will be - the drivers, the authorities who have passed the cost of testing onto motorists or the manufacturers of breathalyser kits who we understand will make millions from this new law. For us, we hope it will be the hundreds of people who will not die unnecessarily due to drink driving.