In 1930, the General Conference of the International Labour Organization adopted a convention restricting forced or compulsory labor. Under Article 11 of the Forced Labour Convention of 1930, only men ages 18 to 45 could be subject to forced or compulsory labor. Article 11 further declared that the proportion of men subject to forced or compulsory labor could be set at no more than 25% of resident adult able-bodied males. The Convention established requirements for determining the proportional of adult able-bodied males who could be subjected to forced or compulsory labor:

In fixing this proportion the competent authority shall take account of the density of the population, of its social and physical development, of the seasons, and of the work which must be done by the persons concerned on their own behalf in their locality, and, generally, shall have regard to the economic and social necessities of the normal life of the community concerned.

Article 11 also required “the maintenance in each community of the number of adult able-bodied men indispensable for family and social life.” Penal systems dispose far less than 25% of adult able-bodied males, but penal systems do encompass some women. The United States has a world-leading prevalence of incarceration. The Forced Labour Convention suggests that public deliberation could conclude that a far higher share of men are potentially disposable than are currently in prison in the U.S.

The Forced Labour Convention set no restrictions on the forced or compulsory labor of men who are not “able-bodied.” Men who are not “able-bodied” apparently would include disabled men and old men. Perhaps the Forced Labour Convention considered all such men to be disposable. Alternatively, the underlying assumption may have been that such men have no public value, and hence would not be subject to forced or compulsory labor.

The Forced Labour Convention of 1930 remains in effect. It has been ratified by 175 countries out of 183 Internation Labour Organization (ILO) member countries. The United States never ratified the Forced Labour Convention of 1930.

The ILO also established the Abolition of Forced Labour Convention of 1957. This convention abolished forced labor for particular prohibited purposes. Those prohibitions apply equally to the labor of all men and women. The United States ratified the Abolition of Force Labour Convention of 1957 in 1991. The Abolition of Forced Labour Convention of 1957 does not clearly supersede the Forced Labour Convention of 1930. For signatory countries to the later convention, the sex-differentiated restrictions on forced or compulsory labor continue to apply.