Latin American Research Review, Vol. 46, No. 2. © 2011 by the Latin American Studies Association. RESEARCH REPORTS AND NOTES RESEARCH NOTES FROM THE UNDERWORLD The Entry Logs of the Rio de Janeiro Casa de Detenção, 1860–1969 Amy Chazkel City University of New York, Queens College Abstract: The Rio de Janeiro state archive’s collection of entry logs for the city’s central detention center, going back to the mid-nineteenth century, provides a rare glimpse into the lives of Rio’s—and Brazil’s—poor and working classes who otherwise left few written records behind. During the time when the institution maintained the entry logs, police exercised broad power to make arrests. Although relatively few detainees were ever prosecuted or even formally charged, the deten- tion center kept detailed records of detainees’ physical appearance, attire, home address, nationality, sex, af iliation, and so on, as well as information about any criminal charges. This article explores the wealth of empirical data that the entry logs provide. It also suggests how scrutinizing this type of document across time shows how record keeping itself changed, in turn affording researchers rare insight into the inner workings of modern Latin American society. I thank Flávio Santos Gomes, Carlos Eugênio Líbano Soares, Gino Negro, Paul Kramer, John Collins, Luciana Pinheiro, and the staff of the Arquivo Público do Estado do Rio de Janeiro—especially Paulo Knauss, Gabriela Maria Costa da Silva, and Johenir Jannotti Viégas—for their help and advice with this research. I also acknowledge the support of the David Rockefeller Center for Latin American Studies at Harvard University and the Profes- sional Staff Congress–City University of New York Research Award Program for helping fund this research. I am also grateful to the three anonymous LARR reviewers, who pro- vided valuable suggestions to improve this article.