Yearly evolution of police efficiency in Spain and explanatory factors

This work aims to study the efficiency of Spanish police forces in the 2001–2006 period, using Data Envelopment Analysis (DEA). Several Malmquist indices are also estimated in order to detect and explain the dynamic variations in efficiency for each of the 52 Spanish provinces into which the territory of Spain is divided. To measure police efficiency, we have considered both solved crimes–those offences against property, public safety, the person, and sexual liberty and indemnity–and the number of police members. In addition, in order to avoid biases in the analysis, and according to the results of a truncated regression, we have considered several exogenous variables which negatively influence police efficiency, such as area, immigration rate and youth index. The findings obtained point out that the average police efficiency for the period analysed reaches 86%, showing optimal behaviour in 55% of the police stations analysed. Additionally, 45% of them increase their productivity yearly.