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Evaluation of the Effectiveness of Automobile Parts Marking on Preventing Theft: Revised Final Report

NCJ Number
Date Published
July 1999
32 pages

This study focused on the effectiveness of Federal laws intended to address auto theft by requiring automobile manufacturers to mark 14 component parts of certain automobile lines with identifying numbers.


Both laws permitted the Department of Transportation to grant a limited number of exemptions for new automobile lines equipped with selected anti-theft devices. The study’s first part examined national auto theft data using a cross-sectional time-series design and data from the Federal Bureau of Investigation and R.J. Polk Inc. for models from 1981 through 1995. The second part examined the experiences and opinions of 47 auto theft investigators regarding the effectiveness of anti-theft labels. The 47 investigators represented 31 of the 32 largest cities, 6 smaller municipalities, and 9 State agencies. Results indicated that parts marking would be cost-effective for high-theft vehicles if extended to cars marked as of 1995. Results also indicated that auto theft investigators supported parts marking and prefered it to the use of devices such as alarms and smart keys. All but one investigator felt that the parts marking legislation should extend to all automobile lines and to all types of noncommercial vehicles, especially pickup trucks. Most would also like the legislation extended to commercial vehicles and additional parts. Findings suggested that anti-theft labels on component parts assisted most investigators in arresting and prosecuting car and parts thieves, although their opinions were divided regarding the deterrent effects of labels on auto theft. The study concluded that the estimates were not sufficiently precise to permit definitive conclusions regarding the cost-effectiveness of marking or whether anti-theft devices are good substitutes for parts marking. Tables, figures, and 10 references

Date Published: July 1, 1999