^aNational CARS Project, Office of Crime Statistics and Research, GPO Box 464, Adelaide 5001, Australia. E-mail: Kriven.Sophie@saugov.sa.gov.au

Abstract

Motor vehicle security has improved considerably in the past decade, both in Australia and other developed countries, and from July 2001 all new passenger vehicles sold in Australia were required to be fitted with an Australian Standard engine immobilizer prior to sale. Although little formal evaluation of the effect of engine immobilizers has been undertaken, Brown and Thomas investigated the effect of a similar initiative introduced in the European Union in 1998. They found that in the U.K., immobilizers were effective in reducing vehicle theft rates, but also that there was some evidence of a displacement in thefts towards older, non-immobilized vehicles. This study replicates the method of Brown and Thomas using Australian data from the National Comprehensive Auto-theft Research System Project, and shows that immobilizers are associated with a strong decline in motor vehicle theft in Australia in recent years. There is also some evidence of displacement towards older vehicles, particularly for unrecovered thefts. Improvements in vehicle security are thought to account for this displacement among newer vehicles, but it is not clear what accounts for this shift among older vehicles. Some potential causes are discussed.