How effective are mandatory breath tests in stopping drunk driving?
Newswise — Tsukuba, Japan — Mandatory breathalyzers could be an effective way to stop drunk driving. However, Japanese researchers have found that without proper implementation, breath testing can make little difference in the number of alcohol-related crashes.
Following several high-profile crashes in the early 2000s that ended in tragedy, drunk driving began to attract attention across Japan. Tougher penalties for drunk driving were introduced and the legal blood alcohol level was lowered. Subsequently, in May 2011, commercial drivers who transport either passengers (bus or taxi drivers) or goods (truck drivers) for a fee were required to take a breath test at the start and end of their shift. There has recently been discussion of extending this requirement to certain categories of non-commercial drivers.
“Now that mandatory testing for non-commercial drivers is being considered, it is important to understand how effective this policy has been in addressing the problem of drink-driving among commercial drivers,” says the lead author of the report. study, Professor Masao Ichikawa. “We wanted to see what difference this policy made in the number of drunk driving crashes involving commercial vehicles.”
To do this, the researchers looked at annual crash data to establish trends in alcohol-related crashes. Since breath testing was made mandatory for commercial drivers but not for non-commercial drivers in 2011, it was possible to compare trends for the two groups to see the effectiveness of this measure.
“The results were somewhat surprising,” comments Professor Ichikawa. “We found that the alcohol-related crash rates for commercial and non-commercial drivers were actually very similar for the period from 2011 to 2020.”
In fact, the trends for commercial and non-commercial drivers have been broadly similar over the past two decades. There was a significant downward trend from 2001 – when legal penalties for drunk driving began to be tightened and the public began to take the problem more seriously – to 2012. 2012 to 2020 , both groups saw neither an increase nor a decrease in the number of alcohol-related crashes.
“Our results suggest that the breathalyzer policy has not been effective. This is likely because of the way it is implemented – drivers are only tested at the start and end of their shift. work and can simply call in to signal themselves sober if they start or end their shift away from headquarters,” Ichikawa says.
There is clearly a need to find more effective ways of ensuring that drivers are not under the influence. One approach that requires further investigation is that of ignition interlocks, which means the driver’s breath must be tested to ensure they have not been drinking before they can start the vehicle.
This work was supported by JSPS KAKENHI [Grant Number 21H03195]. Dr. Katanoda was awarded a JMWH Bayer Fellowship from September 1, 2017 to August 31, 2019.
The article “Trends in alcohol-related crashes before and after the introduction of mandatory breath testing for commercial truck drivers” has been accepted for publication in the Journal of Epidemiology at DOI: 10.2188/jea.JE20220054