The National Institute of Forensic Toxicology (NIFT) in Oslo receives
blood samples from all Norwegian drivers suspected of driving under th
e influence of alcohol. It is well known that a large proportion of th
e arrested drunken drivers are repeat offenders. The purposes of this
investigation was to find the arrest rates (the percentage of subjects
arrested once or more) among drunken drivers followed retrospectively
and prospectively during the Ii-year period 1984-1994 and the probabi
lity of 'abstaining' from becoming a recidivist during the 9 years sub
sequent to the year of selection. By examining the rearrest rates duri
ng the 3 following years for drivers selected in 1986, 1989, 1991 and
1992 we tried to look for major effects due to the change in the Norwe
gian road traffic act of 1988. Altogether 45% of the selected drunken
drivers were arrested two or more times. Totally the '9-year survival
rate' (i.e. not being rearrested) was 60% for drivers with blood alcoh
ol concentration (BAG) selected from the interval 0.06-0.09%; 56% from
BAC 0.13-0.16% and 51% from 0.26-0.29%. The data were further evaluat
ed with respect to frequency of rearrest during 3 years after selectio
n, and was around 30% in 1986, while it was lower for drivers selected
in 1992 (19%). An explanation for the reduction in rearrest rate may
be the changes in the road traffic act which took place in 1988. (C) 1
998 Elsevier Science Ireland Ltd.