The impact of crack on variations in robbery, burglary, and homicide rates in the United States was investigated using a two- stage hierarchical linear model that decomposed between-and- within city variations in crime rates for 142 cities.
The first level of the model represented changes in crime rates within each city over time, whereas the second level of the model reflected differences between cities in these trends. Data used in the analysis include Uniform Crime Reports; an indicator of levels of crack involvement; and measures of resource deprivation, population composition, and family structure for the 142 cities. Robbery, burglary, and homicide data were obtained from the Federal Bureau of Investigation for offenses reported to the police in each jurisdiction between 1984 and 1992. The measure of crack involvement used the highest drug arrest rate for each city between 1986 and 1989, the time period during which crack appeared in most U.S. cities. Census data from 1980 and 1990 were used to examine the influence of both general structural conditions and changes in these conditions on levels of and trends in robbery, burglary, and homicide rates. Results showed cities with higher levels of crack use experienced larger increases in robbery and decreases in burglary. Cities with greater levels of crack use had higher homicide rates but did not show more rapid increases in these rates than other cities. The emergence and proliferation of crack appeared to shift the balance of urban offending opportunities and rewards from burglary to robbery. The ability of the findings to explain recent decreases in violent crimes in many U.S. cities is discussed. 49 references, 6 notes, 4 tables, and 2 figures