Abstract
Compulsory schooling laws are often suggested as a means of combating youth crime, but little is known about how effective they are in emerging economies. Using the exogenous changes in compulsory high school enrolment after the 2009 Brazilian Constitutional Amendment 59, we investigate its impact on youth crime indices, violent and less violent ones. We compared municipalities that received federal funding to increase high school enrolment with those that did not, using difference-indifference models to estimate the effects on selected youth crime indices. Our findings suggest that the Amendment had little or no effects on reducing youth crime. We observe small crime reduction when the incapacitation effects of the Amendment were largely outweighed by the negative effects of sudden overcrowding in classrooms with overburdened teachers providing inadequate supervision, and insufficient crime monitoring in public schools with shorter school hours. Adverse effects of overcrowding were worse in poor municipalities with more disadvantaged students and fewer resources that exactly balanced out the incapacitation effects, producing zero effects on crime. The effectiveness of compulsory schooling laws in reducing youth crime thus depends on the balance between the incapacitation effects and overcrowding effects.