The total number of DUI arrests in Illinois fell from about 55,100 in 1986 to 48,656 in 1988. Measures that may have reduced this number include the summary suspension upon arrest of the DUI offender's license and increased minimum penalties for repeat DUI offenders. Further, a law enacted on January 1, 1989, allows police departments to impound the vehicle of a person arrested for DUI for up to 6 hours. Under a 1986 law, persons arrested for DUI automatically have their licenses suspended for 3 months if they register a blood alcohol concentration of 0.10 or greater. Also, the license of a person charged with DUI may be revoked for 1 year if the person is involved in an accident that causes a serious injury or fatality. The most common disposition for DUI offenders involves court supervision and remedial education (50 percent); the second most common disposition is conviction (33 percent), and most of those convicted receive probation. Despite stricter penalties, tougher enforcement, and the decline in DUI arrests, more than 570 alcohol-related fatalities occurred in Illinois during 1987. The Illinois Secretary of State's Office estimates that about 50 percent of all traffic fatalities are alcohol-related. 1 figure.