Late-night drink laws saved many young lives
Hundreds of young people have escaped death on Britain’s roads after laws were relaxed to allow pubs to open late into the night, a study has found.
The number of crashes reported to police fell by 13 per cent, or 1,643 a month, after licensing laws were reformed in 2005, according to the first such analysis of official data.
The decline has been felt most sharply among drivers aged between 18 and 25 and has been most marked on Friday and Saturday nights. Accidents involving young drivers at those times have fallen by 33 per cent.
There are plausible reasons why extending opening hours might reduce road accidents but there are also plausible reasons why it might increase road accidents. The authors discuss them at the start of the study (PDF).
First, extended hours may influence the intensity of drinking (the number of impaired bar patrons). Thus, if patrons spend longer at the bar and drink the same total amount as before the longer hours, the intensity could decline as they no longer drink to beat the clock.
Alternatively, the longer period could allow a larger share of drinkers to become impaired and so intensity could increase. The second influence works through the amount and timing of driving among the impaired patrons. As we’ve suggested, the later closing hour may reduce the driving to illegal pubs or home parties as patrons stay in the pub.
Moreover, if the bar no longer goes instantly from full to empty at the early closing hour, there may be fewer impaired drivers simultaneously on the road, even if the total number of impaired drivers is the same. In addition, the impaired drivers may now drive later in the night when fewer other drivers are on the road. While these influences may suggest fewer accidents, it could be the case that those who leave the bar very late have less access to public transit and are more likely to drive.
In the end, we find the arguments each way at least plausible and view the direction of the influence as an empirical issue.
To get to the empirical meat, they use data from the Department of the Environment, Transport and the Regions "that contain all motor vehicle accidents reported to the police from 2002 to 2008 for all 416 local jurisdictions in the three parts of Britain."
We know the type of accident (whether it caused either serious injury or a death), the date and time of the accident, location of the accident and the age of the driver of any vehicle involved in the accident. Critically, the data allow us to accurately assign accidents to the pre and post policy period.
The results are striking and there are several reasons to think that the correlation with the Licensing Act implies causation. Firstly, there is a sharp reduction in road accidents in the months immediately following the start of so-called '24 hour drinking'. Secondly, the rate of accidents remains significantly lower than the pre-liberalisation period thereafter. Thirdly, the data from Scotland—used as a control—doesn't follow the same pattern at all. On the contrary, Scotland saw rates falling before the enactment of the legislation (which affected England and Wales, but not Scotland) and then flattening out. This suggests that there is no unidentified third variable that reduced road accidents in the UK as a whole.
The authors conclude that "the policy is associated with a 9.8% decrease in the number of accidents per jurisdiction." The results are statistically significant and remain robust despite the researchers throwing numerous tests at them. Indeed, the results become stronger as they dig further into the data. It becomes clear that the decline in road accidents is concentrated late at night, at weekends and amongst young people.
When we look at night hours the decrease is slightly higher at 14%. These night hours can be further divided into those on the weekends and during the weekdays. The weekday decrease is 12% as shown in row 3 while the Friday and Saturday decrease is 18% as shown in row 4.
... We next examine the hours of 9:00 at night to 3:00 in the morning on Friday and Saturday nights. As shown in the fourth row of Table 3, the estimated decline remains statistically significant and represents a 23% decline. Similarly, an even narrower window of 11:00 at night to 3:00 in the morning on Friday and Saturday nights shows a nearly 24% decline in accidents. Thus, at the very hours when one might anticipate patrons would otherwise be simultaneously streaming out of bars and into cars, the new legislation allows them to remain in the bar and spreads out their dispersal with a large apparent decline in traffic accidents.
... The estimates reveal that the decrease in accidents associated with longer hours is concentrated almost entirely among young drivers... As a percentage decrease, a drop of .380 represents a 32.5% decrease for younger drivers on Friday and Saturday nights. While the coefficient is negative for middle age drivers, it is not statistically different from zero. The coefficient for older drivers is not significant, vanishingly small and actually positive. Thus, the clear pattern is that the age group most influenced by the policy change is the youngest drivers.
It's interesting to compare this study with the crude ecological studies that I have often written about in the past (such as the English heart miracle, the Canadian minimum pricing scam and, most recently, the Colorado casino miracle). These studies use aggregate data such as hospital admissions and attribute the reported decline to legislation (invariably, legislation that the researcher supports). One problem with this approach is that there are all sorts of other variables that could confound the results. Another problem is that some outcomes (such as heart attacks) are in long-term decline and would have fallen with or without the legislation.
In the case of road accidents in the UK, there is no doubt that they have been in decline for decades, albeit with significant fluctuations (they have risen recently, for example, and they were rising immediately before the Licensing Act came into force). The authors acknowledge this and their conclusions are based on a clear and sharp drop that coincided with the liberalisation of the licensing laws.
But aside from taking the same basic approach, this study has nothing in common with the policy-based ecological studies that I have criticised in the past. The real problem with those studies is that they either cherry-pick a small sample of the population while ignoring the national data (eg. here, here and here) or that they are based on a computer model that bears no relationship to the actual data (eg. here, here and here). Sometimes they even pretend the legislation started when it didn't just to make the facts fit (eg. here and here). Oh, and they hardly ever use a control group.
This study doesn't pull any of those tricks. It examines all road accidents in England and Wales over a seven year period and compares them to a control group (Scotland) that is directly comparable. It shows a clear decline in rates directly following the enactment of the legislation and it shows that this decline was followed by a consistently lower rate thereafter.
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| Trends in England and Wales (top) compared with trend in Scotland (bottom) |
They show all this using real—not modelled—data and they compare the results in England and Wales with real data from another real country, Scotland, not with a hypothetical model of what might have happened in the absence of legislation.
Moreover, the lead author is an economist who has written about a broad range of issues, not a single-issue campaigner with a known bias. Indeed, he has previously authored a study that reported a negative effect of the Licensing Act (ie. absenteeism). He kicks the wheels pretty hard with a series of tests to make sure the findings are robust. It could, of course, still be a coincidence, but the evidence that extending drinking hours in England and Wales had a positive effect on road accidents looks strong.
