Sex Ratio of Prisoners Across the World: Taking Gender Seriously

face of a prisoner

Most prisoners are men. Prisoners worldwide numbered 10.1 million persons on a given day about the year 2010. Among those prisoners, about fifteen men were in prison for every woman in prison.

The sex ratio of prisoners is significant. Punishment is a fundamental political responsibility. Prisoners are among the poorest of the poor in human welfare. Prisoners should be an important public concern. Common human groups such as families and communities usually have a roughly equal sex composition. The sex ratio of prisoners is extremely far from equal.

The sex ratio of prisoners isn’t immutable biological destiny. Across 45 international jurisdictions for which data are available and covering 22% of the world’s 2010 population, the aggregate sex ratio of prisoners fell from 20 men prisoners per woman prisoner to 13 men prisoners per woman prisoner from 1977 to 2010. Data are available from 2003 and 2010 for 177 jurisdictions covering about 94% of the world’s population. From 2003 to 2010, the aggregate prisoner sex ratio fell from 15.7 men in prison per woman in prison to 14.5 men per woman.

Considerable variation exists in the sex ratio of prisoners across the world. Among jurisdictions holding more than 1000 prisoners about 2010, Pakistan had the highest sex ratio: 82 men in prison per woman in prison. India, closely related to Pakistan geographically and historically, had only 23 men in prison per woman in prison. Taiwan was among the jurisdictions closest to sex equality: it had only 4.6 men per woman imprisoned. South Korea, in contrast, had 17.5 men in prison per woman in prison. Most persons would readily notice such sex-ratio differences in ordinary human groups.

The sex ratio of prisoners is relatively high in Sub-Saharan Africa and in low-income countries. Sub-Saharan Africa in aggregate had 30 men in prison per woman in prison about 2010. North America, East Asia, and Pacific had in aggregate 12 men in prisoner per woman in prison. These regional differences correlate with income differences. Low-income jurisdictions had in aggregate 21 men per woman in prison, while the corresponding figure for high-income countries is 12. Even controlling for income group, Sub-Saharan Africa had on average a 55% higher prisoner sex ratio than did East Asia and the Pacific.

Large international differences in the sex ratio among prisoners are not easy to explain. Across 209 international jurisdictions about 2010, the median prisoner sex ratio was 21.2 men in prison per woman in prison. Among those jurisdictions, 25% had a sex ratio less than 14.2, while 25% had a sex ratio greater than 34.7. Indicators for region and income group together explain only 20% of the variation in the logarithm of the sex ratio. Adding to those indicators the urban population share, the labor force participation shares of men and women, and the Human Development Index raises the explained variance only to 34%.

Human biological sex differences, gender, and the socio-economic environment allow large variation in prisoner sex ratios. Considerable variation in prisoner sex ratios exists internationally as well as within particular jurisdictions. High ratios of men in prison per woman in prison are a social justice failure.

Prisoners Ignored in International Development Policy

face of a prisoner

Work on human development has emphasized the capabilities that every human being, male and female, should have. An influential study on development has eloquently declared:

Human beings are the real ends of all activities, and development must be centered on enhancing their achievements, freedoms, and capabilities. It is the lives they lead that is of intrinsic importance, not the commodities or incomes they happen to possess.^

Persons in prison often have little choice in the food they eat and the clothes they wear. They typically do not have the freedom to move beyond the confines of a single building, or even within that building. Their opportunities to meet other persons and to learn about the world are highly constrained. With respect to human capabilities, prisoners are among the poorest of the poor.

The United Nations’ Human Development Index (HDI) is a leading quantitative measure of human development. The HDI measures three dimensions of human development:

leading a long and healthy life, measured by life expectancy at birth; being knowledgeable, measured by literacy and school enrollment; and having a decent standard of living, measured by GDP per capita ^

These measures of human development indicate persons’ capabilities to exercise freedom. As a United Nations Human Development Report has emphasized, “Human development is about freedom.”^ Being confined in prison highly constrains persons’ freedom.

The Human Development Index correlates positively with the prevalence of imprisonment across jurisdictions worldwide. Across 182 jurisdictions covering 98% of the world’s population, the HDI for 2011 has quartiles 0.52, 0.70, and 0.80. A 0.10 increase in the HDI is associated with a 21% increase in the prevalence of imprisonment. The HDI is even more strongly correlated with the prevalence of imprisonment controlling for region and income-group fixed (level) effects on imprisonment prevalence. Imprisonment prevalence might increase human development of the non-imprisoned population (most of the population) through increases in their personal security. More realistically, states with strong public administrative capacity are likely both to foster better human development outside of prison and to hold a larger number of persons in prison.

Despite prisoners’ significance to ideals of human development, prisoners are largely invisible in international development policy. The human development of prisoners is much more directly related to public policies than human development of persons generally. The HDI’s positive correlation with imprisonment prevalence deserves careful consideration. Acknowledging significant human trade-offs in human development is a step toward making those trade-offs as just and humane as possible.

Gender Inequality Index Relative to the Prisoner Sex Ratio

face of a prisoner

Countries with a higher level of gender inequality tend to have more inequality in the ratio of men in prison to women in prison. The United Nations’ Gender Inequality Index (GII) compares male and female parliamentary representation, labor force participation, and attainment of secondary and higher education. It also includes measures of maternal mortality and adolescent female fertility relative to particular reference norms. The GII, like development policy generally, doesn’t consider male and female imprisonment. It doesn’t recognize large, worldwide inequality in the ratio of men in prison per women in prison.

The United Nations’ Gender Inequality Index correlates positively but imperfectly with inequality in the prisoner sex ratio. Moving from the 2011 median country-value for the GII to the 75th percentile is associated with a 15% increase in the ratio of males to females in prison.  The prisoner sex ratio, however, is 56% greater at its 75th percentile relative to its median value. The GII and the prisoner sex ratio are different but correlated measures of gender inequality.

Gender inequality in the sex ratio of prisoners concerns the most directly and personally punishing outcomes of public policy. The GII, in contrast, encompasses elite statuses: the sex ratio in parliamentary representation and in degrees received in higher education. The prisoner sex ratio is a more appropriate focus for welfare concern about gender inequality in human development.

The Gender Inequality Index has more uncertainty in its measurement and is more complicated and difficult to understand than is the sex ratio of prisoners. Measuring labor force participation requires a country-wide survey. Measuring maternal mortality and adolescent female fertility requires compiling nation-wide birth and death data with record-specific information on sex, age, and cause of death. Measuring the level of formal education in the population requires a long-form national survey. Understanding the actual calculation of the GII requires the ability to parse complicated mathematical formulas and some understanding of index-number theory. A specific value of the GII has no specific meaning to most persons. The sex ratio of prisoners, in contrast, requires collecting information only from political bodies authorized to imprison persons. The prisoner sex ratio is simple to calculate and easy to understand.

Just as for inequality in economic growth generally, the weight of welfare concern about gender inequality across population groups is a matter of justice. More concern for the parliamentary sex ratio than for the prisoner sex ratio indicates lack of concern for the poor.