This article examines cross-sectional and longitudinal differences in police strength between nations over the past decade.
For the purposes of this discussion, "police strength" is used to describe "the number of police officers and/or police employees in a particular organization or jurisdiction." This study of differences in police strength among nations is the first product from a broader research agenda with three goals. First, after collecting data from a large number of nations, researchers will explore the factors that account for differences in police strength among nations. Second, after compiling a longitudinal data series on police strength over the past decade, researchers will explore why some nations are experiencing a period of increasing police strength while other are in decline, and others are in a period of stability. Finally, researchers intend to draw some inferences about whether the global policing industry has experienced a period of growth or decline relative to the world population over the past decade. The current article first reviews what is known about police strength, its definition, the theories used to explain it, and the methods used to study it. The authors then assess the current state of international data on police strength. Significant data problems make it difficult to draw much more than weak inferences about differences in police strength over time and place. After discussing these data problems, the article describes the development of the International Police Strength (IPS) file from numerous sources. Using the IPS data, the authors then describe national differences in police strength relative to the size of the population. They also offer some tentative conclusions about the growth of the world's policing establishment. A number of recommendations for future research and theory on this issue are offered. 5 tables, 1 figure, and 40 references