Increases in traffic accidents that accompanied increases in vehicle use in the decade after World War II led in the 1960's to increases in the numbers of police and increasing penalties for traffic offenders. The nation later also established education for new drivers, traffic offenders, and pedestrians. The Traffic Infraction Notification System, which provided for fines as an alternative to criminal court proceedings, has handled most of the minor offenses. Serious offenders have often been sentenced to prison. In recent years the criminal justice system is handling traffic offenses more often and more severely than before. The changes in law enforcement appear to have affected traffic safety, with traffic accidents declining by 44 percent in the early 1970's, remaining stable after 1975, and slightly increasing in the early 1980's. Tables, notes, and reference lists.