The War Labor Board (WLB) and its predecessor, the National Defense Mediation Board, had a profound impact on relations between employers and unions during World War II. The WLB—made up of representatives from government, labor, and management—provided protection for unions from hostile bosses, increased the wages of the lowest-paid workers, helped set industry-wide wage patterns, and established methods of resolving shop floor disputes. Although the WLB operated in routinized and bureaucratic ways, its decisions could also carry powerful ideological messages. That became clear in the following document, which insisted upon the policy of equal pay for equal work—a seemingly self-evident principle that was not standard practice in American industry. This board decision mandated equal pay for women.
The application of the Order [General Order No. 16; Adopted 24 November 1942] is quite plain and simple in cases where women are employed to replace men on jobs which are not changed. Where the plant management, in order to meet the necessity of replacing men by women, has rearranged or lightened the job, perhaps with the employment of helpers to do heavy lifting or the like, a study of job content and job evaluation should afford the basis for setting “proportionate rates for proportionate work.” Such questions require a reasonable determination, by collective bargaining or arbitration, of the question whether, or how far, the newly arranged job is of equal quantity and quality with the old job. The new wage set on such a basis does not require the approval of the National War Labor Board under the terms of General Order No. 16.
We have found from experience that there has been some tendency to abuse this rule of equal pay for equal work.
This refers particularly to job classifications to which only women have been assigned in the past. The rates for such jobs, especially when developed by collective bargaining, are presumed to be correct in relation to other jobs in the plant.
Whether a job is performed by men or women, there may be a dispute over correctness of its wage rate in relation to rates for other jobs in the same plant. These are the so called intra-plant inequality cases. Their discrimination should not be related to the “equal pay for equal work” question; they should be determined on the basis of maintaining or developing a proper balance of wage rates for various jobs based upon job evaluation.
We have even seen instances in which the workers have demanded or the employers have proposed, that the wages being paid to women in one plant should be increased on the ground that in some other plant similar work is being done by men at a higher wage. Such proposals tend to overlook the fact that wages paid to men in the same occupation generally vary from plant to plant. In such cases, the question whether the work is done by men or women is irrelevant. The claim for increased wages immediately reduces itself to a single question of different wage rates for the, same work in different plants. Interplant inequalities in wage rates are quite common in American industry, and often well established. They afford a basis for a wage increase only in very exceptional cases. If the interplant inequality is in fact one that should be corrected at all, its correction is independent of any question of men and women workers.
Source: National War Labor Board Press Release, No. B 693, June 4, 1943, in “Chapter 24: Equal Pay for Women,” The Termination Report of the National War Labor Board: Industrial Disputes and Wage Stabilization in Wartime, January 12, 1942-December 31, 1945, vol. I, 290–291.