• traffic law
• alcohol
• breath testing
• drinkdriving

The National Police Agency reported in June 2003 that the number of fatal crashes caused by drunken drivers had decreased by 30% in the 12 month period after the change of the traffic law.¹ The number of alcohol related fatal crashes in the period from June 2001 to May 2002 and that in the same period of 2002–2003 were 1187 and 830, respectively. In addition, the number of drivers found guilty of driving under the influence of alcohol was reduced by 7% (from 218 377 to 202 985) during the same period.

In Japan, the Traffic Act was changed and the new law took effect in June 2002. The legal limit for alcohol concentration while driving was lowered and penalties became tougher under the new law. Moreover, it became much harsher on drivers who committed the most serious offenses.

Drunken drivers have been defined in Japan by the level of alcohol measured by breath test. The new act lowered the breath alcohol concentration at which it is illegal to drive a motor vehicle from 0.25 mg/l breath to 0.15 mg/l breath. Given the fact that in the United Kingdom the legal limit for drink-driving is 0.35 mg/l breath, which is equivalent of the legal limit of blood alcohol concentration (BAC) at 0.08%,² this limit of 0.15 mg/l breath seems stricter than other industrialized countries and actually requires “zero tolerance”.

Motorists convicted of drinking and driving can be sentenced to up to three years in prison and fined up to Yen 500 000 (US$4250). They can have administrative penalties imposed, such as license suspension or revocation, and penalty points according to the range of alcohol concentration.

Lowering the legal limit is a proven effective countermeasure that will reduce alcohol related traffic fatalities, especially combined with more severe penalties and enhanced enforcement.³ However, the extent to which these measures can reduce injuries is not known. It may vary between nations, since drivers’ attitudes are influenced by many factors. Ten years ago, there was an Australian study that showed a remarkable effect—the proportion of drunk-drivers involved in accidents fell by one third in the year when the 0.08% BAC limit went into effect.⁴

To implement such a strong measure, public support is essential. Movements against drunk-driving have been rapidly developing in Japan since 1992, when two children were killed by a drunken driver on the Tohmei Super Express Way and the victims’ parents started a petition. Thereafter, public awareness has been raised and most people support “zero tolerance” to drunk-driving.